Tokyo Olympics relay gold medallist Briana Williams got her birthday celebrations off to an early start this week.

The 2021 Formula One title race was one for the ages.

Fortunately, the release of season four of Netflix's 'Drive to Survive' series is landing on Friday, giving fans the opportunity to relive the drama and whetting appetites for the forthcoming 2022 campaign.

Few will forget how last season ended, with Max Verstappen pipping Lewis Hamilton in scarcely believable circumstances on the final lap of the final race.

But there had been controversy throughout the year even before that point, making the latest edition of one of sport's great documentaries a must-watch.

Fans will be desperate to learn how 2021 played out behind the scenes, but what should they be looking for? Stats Perform picks out five flashpoints.

Silverstone contact sets the tone

A back-and-forth title tussle between Verstappen and Hamilton was already nine races old by the time the teams arrived at Silverstone – at which point the 'Drive to Survive' producers must have thought they had hit the jackpot.

Hamilton ended a five-race barren run for Mercedes with victory in his home race, but only after sending Verstappen into the barriers at Copse Corner on lap one – a 10-second penalty of little consolation to Red Bull, whose team principal Christian Horner slammed the 2020 champion's "dirty driving".

Seeing the reaction on the pit wall would be of interest to any fan, although this clash merely teed up the drama to come.

Mixed fortunes for furious Lewis in the wet

Two races last year descended into chaos due to the weather, with Verstappen winning in Belgium while Hamilton triumphed in Russia, benefiting from Lando Norris' spin in the rain for his 100th victory. That Sochi result cancelled out events at Spa, where Hamilton had been far from impressed.

Viewers will likely learn more about developments at the 2021 Belgian Grand Prix from 'Drive to Survive' than from live coverage at the time, as the race lasted just two laps under a safety car following Sunday rain.

That was enough to declare a result with half points, with Verstappen rewarded for pipping breakout star George Russell to pole. In public, Hamilton fumed it was "all a money scenario", and it is unlikely he was any calmer in private.

McLaren one-two after halo saves Hamilton

Between Belgium and Russia was the Italian GP at Monza, with perhaps the scariest moment of the season. Verstappen's battle with Hamilton went a little too far as he rode over the Briton's car, with the Mercedes halo required to keep the driver from serious harm.

"I am so grateful I am still here," said Hamilton after being forced to retire, with Verstappen later following him back into the garage.

The documentary cameras surely could not miss this key moment in the title race, but 'Drive to Survive' has been hugely successful in picking out narratives right down the grid – and this was a notable weekend in the midfield, as McLaren profited with a one-two courtesy of Daniel Ricciardo and Norris.

Hamilton heroics at special Sao Paulo GP

Verstappen arrived in Brazil 19 points clear of Hamilton with four races remaining, and the odds were increasingly stacked against his rival over the course of the weekend at the Sao Paulo GP.

Hamilton served a five-place grid penalty when his qualifying time – the fastest on the grid – was struck off for a DRS infringement, meaning he had to start from 10th even after recovering from 20th to fifth in the sprint race. Verstappen escaped punishment when he forced the Mercedes man wide in the main race, too.

Remarkably, Hamilton still won, with Toto Wolff claiming the various setbacks had "woke up the lion". There would have been no final-day spectacle if not for the Briton's late-season charge, which started in Brazil.

Two weeks of epic drama decide title

The final episode of the season will surely focus on the decider in Abu Dhabi, where race director Michael Masi's application of the rules infuriated Mercedes as Hamilton was denied a record-breaking eighth championship in fairly ridiculous fashion.

Footage from that race should entertain even F1 sceptics, with Wolff likely to play a prominent role having pleaded with Masi not to make the contentious call that cost Hamilton and crowned Verstappen.

But the stakes were only such because the pair had entered that race all square in the standings – only the second time this had ever happened – after a similarly eventful Saudi Arabian GP.

Verstappen could have wrapped up the title with time to spare but lost out to Hamilton after a qualifying crash, two red flags and a succession of safety cars, hinting at the level of incident that was to come the following week.

Red Bull team principal Christian Horner disagrees with the decision to remove controversial Formula One race director Michael Masi.

Masi was offered a new role elsewhere in the FIA after being replaced by two men in Niels Wittich and Eduardo Freitas for the 2022 season.

The Australian official was at the forefront of the controversy surrounding Max Verstappen's title triumph last year.

Verstappen pipped Lewis Hamilton in the final lap of the final race, but he was only able to stage that late recovery after Masi let the cars between the pair – running first and second but separated by a series of lapped rivals – pass a safety car and allow one lap of racing.

Verstappen, on fresher tyres, prevailed, prompting a protest from Hamilton and Mercedes that failed – although Masi has now been removed from his role.

"It's going to be interesting to see how that works," Horner told BBC Breakfast on Monday.

"For me, you want consistency. Having one race director, for me, was preferential, rather than splitting that role.

"We have a new president [Mohammed Ben Sulayem] who has come in and inherited this situation, and he's looked to impose change.

"It's great that Herbie Blash, a very experienced race control member, is coming back into the fray as well, so we will see how it pans out.

"But I thought it was harsh on Michael Masi that he was replaced after a lot of pressure being put on him. Everything is back to zero, new season, new regulations."

Wittich and Freitas will have to deal with a similarly tense, tight title race, though, according to Horner.

"It has been so intense," said Horner. "I think you might get a couple of other drivers come into that fray as well.

"It was epic last year, and if that continues I think there's going to be some fantastic races in the season ahead.

"It's great for the sport. The sport has never had so much coverage and so much following. The following in the sport has gone exponential over the last season, and that's great to see."

Max Verstappen has signed a five-year contract extension with Red Bull ahead of the 2022 season.

The Formula One world champion's previous deal was due to expire next year, but his team on Thursday announced that the 24-year-old will stay on until at least the end of the 2028 season.

Verstappen claimed his first F1 title in 2021 by pipping Lewis Hamilton in controversial circumstances in Abu Dhabi.

The Dutchman said: "I really enjoy being part of Red Bull Racing, so choosing to stay to the 2028 season was an easy decision. I love this team and last year was simply incredible.

"Our goal since we came together in 2016 was to win the championship and we have done that, so now it's about keeping the number one on the car long-term."

Hamilton had seemingly won a record-breaking eighth crown last year, but Williams driver Nicholas Latifi crashed with four laps to go in Abu Dhabi, leading to the safety car coming out.

When the race restarted there was only one lap remaining and Verstappen was able to start just behind his rival despite Hamilton previously having a significant lead over him. Verstappen’s car had been fitted with new tyres, enabling him to overtake the Mercedes driver and sensationally dethrone his rival.

Verstappen would have likely been in line for a new deal regardless of that incredible outcome at the Yas Marina Circuit, with Mercedes generally seen as the only team that could compete with Red Bull from a financial perspective.

Tension between the two teams in the 2021 campaign – not to mention Mercedes already paying Hamilton a fortune – made a switch to their rivals in the near future highly unlikely.

According to reports, Verstappen's new deal puts his earnings in a similar bracket to Hamilton, with the world champion apparently set to be paid €40-50million (£33-42m) per year – the seven-time champion is said to earn €48m (£40m).

Red Bull and Verstappen will be relieved to have such formalities out of the way in plenty of time ahead of the new season, which is due to begin with the Bahrain Grand Prix on March 20, the weekend after a second round of pre-season testing.

Max Verstappen has signed a five-year contract extension with Red Bull ahead of the 2022 season.

The Formula One world champion's previous deal was due to expire next year, but his team on Thursday announced that the 24-year-old will stay on until at least the end of the 2028 season.

Verstappen claimed his first F1 title in 2021 by pipping Lewis Hamilton in controversial circumstances in Abu Dhabi.

The Dutchman said: "I really enjoy being part of Red Bull Racing, so choosing to stay to the 2028 season was an easy decision. I love this team and last year was simply incredible.

"Our goal since we came together in 2016 was to win the championship and we have done that, so now it's about keeping the number one on the car long-term."

The FIA has expressed pride at the standard of stewarding in Formula One, in response to Lewis Hamilton's earlier comments on the need for "non-biased stewards" in the upcoming season.

Hamilton, who missed out on a record-breaking eighth title in a controversial finale to the Abu Dhabi Grand Prix last December, made the comments at 2022's first testing session in Barcelona.

The 37-year-old lost his title to Red Bull's Max Verstappen in the final seconds of the season, after since-removed race director Michael Masi unlapped a series of cars to permit one final lap of racing, with the Dutchman on new tyres.

Hamilton criticised the officiating of F1 in a news conference, insisting that some drivers "are very good friends with certain individuals" and claiming a requirement for "non-biased stewards".

In response, a spokesman for the sport's governing body said: "The FIA is proud of its global stewarding pathway that connects and develops the most talented stewards from across motorsport."

"This has resulted in a strong, independent and experienced group of officials who carry out their work with impartiality and the utmost professionalism."

Mercedes boss Toto Wolff had earlier disagreed with Hamilton's comments, saying he did not think there was a "conscious bias" towards any teams.

Hamilton completed 50 laps in Mercedes' new W13 car in Barcelona, and will kick-start his attempt to regain the title at the Bahrain Grand Prix next month. Meanwhile, his team are looking to extend their record-breaking run of eight successive constructors' titles, which began in 2014.

Mercedes boss Toto Wolff and his Red Bull counterpart Christian Horner have pledged to move on from the fierce rivalry that engulfed Formula One's leading teams last season.

December's Abu Dhabi Grand Prix saw Red Bull's Max Verstappen win his first Drivers' Championship in contentious fashion, after race director Michael Masi elected to unlap cars between Verstappen and leader Lewis Hamilton, permitting one lap of racing which saw the Dutchman snatch the title in the season's final seconds.

Mercedes reacted furiously to the result and rumours spread that a disillusioned Hamilton could even quit the sport, while Masi was removed from his role ahead of the 2022 season, with two new race directors appointed in his place.

Hamilton, however, will be going for an eighth world title this season and speaking at the first testing session in Barcelona, both Wolff and Horner were keen to draw a line under the events of 2021, and look ahead to the upcoming campaign.

"It [the rivalry] is to be expected," Wolff said in a news conference. "It got fierce at times and brutal, But there's a lot at stake.

"It's a Formula One world championship, there's the fighting on-track, and the fighting off-track for advantages. That's okay.

"But we need to move on. There's been so much talk about Abu Dhabi, it came to a point that it was really damaging for all stakeholders of F1, and we've closed the chapter and moved on.

"Now it's about 2022, the game is on again, all points to zero, new opportunity and new risk."

Lewis Hamilton insisted Formula One must ensure that there is no bias from stewards heading into the 2022 season.

Hamilton was beaten by Red Bull's Max Verstappen in a contentious conclusion to the Abu Dhabi Grand Prix, after race director Michael Masi elected to allow a series of cars to pass a late safety car, permitting one lap of racing with the Dutchman on new tyres.

Masi has since been removed from his role, while rumours abounded that Hamilton could leave the sport, though the seven-time world champion last week confirmed he would be racing once again for Mercedes this season.

Two new race directors will share the role Masi has vacated.

At the first testing session in Barcelona ahead of the new campaign, which starts on March 20 in Bahrain, Hamilton was asked if the changes would result in more consistent decision-making.

"We need to make sure we have non-biased stewards, too," the 37-year-old said.

"Racing drivers, some are very good friends with certain individuals, some travel with certain individuals and tend to take more of a keen liking to some of them.

"I think [we need] people who have no bias, are super central when it comes to making decisions."

Hamilton's belief is not shared by his team's boss, Toto Wolff, however.

"I think we need professionalism in the stewards' room," said Wolff in a news conference.

"I don't think there is a conscious bias to be honest. It's intelligent people."

Red Bull's Christian Horner, who has a not-so-secret rivalry with his Mercedes counterpart, agreed.

"I would agree with Toto that I don't think there's an intended bias. I'm not aware of any stewards travelling with drivers to races," he added.

"In [FIA president] Mohammed [ben Sulayem] we have a new president that is looking to bolster the structure and bring in an equivalent of a VAR [video assistant referee, used in football], and I think giving a better infrastructure for clearer decisions with clearer regulations is something that should be strived for.

"But I certainly don't think there was any bias from any stewards during the last seasons."

Lewis Hamilton has denied reports he was considering leaving Formula One, as the seven-time Drivers Champion looks to bounce back from the controversial finale to the 2021 season.

Hamilton was beaten by Red Bull's Max Verstappen in a contentious conclusion to the Abu Dhabi Grand Prix, after race director Michael Masi elected to allow a series of cars to pass a late safety car, permitting one lap of racing with the Dutchman on new tyres.

Masi has since been removed from his role, while rumours abounded that Hamilton could leave the sport. But, speaking at the launch of Mercedes' new W13 car, Hamilton denied that his return was ever in question.

"I never, ever said that I was going to stop", he said. "I love doing what I do, and it is such a privilege working with this large group of people.

"You really feel like you're part of a team and part of a family, working towards that common goal. There's no feeling quite like it.

"But yeah...it was obviously a difficult time for me, and it was a time where I really needed to take a step back and focus on being present."

Mercedes boss Toto Wolff had previously hinted that Hamilton was left 'disillusioned' by finishing second, but the 37-year-old now claims to be focused on making a successful start to the 2022 season next month.

He also expressed his excitement at working with new teammate George Russell, who has replaced Valtteri Bottas after leaving Williams in the off-season.

"I eventually got to a point where I decided I was going to be attacking, coming into another season working with Toto and George," he added.

"It's exciting seeing George come in and bring his energy. I can already feel that throughout the team. I think it's going to be an exciting season."

The launch of the W13 sees the German constructor return to its classic silver livery after two years using a black colourway, as part of an anti-racism campaign, and the car has been advertised by Mercedes as '98 per cent new' and as 'the product of a complete redesign from top to bottom'.

With the team bidding for a ninth consecutive Constructors' Championship title, Hamilton is keen to ensure standards remain high.

He said: "Naturally, every single individual within this team has worked towards the ultimate goal of winning the world championship, raising the bar and doing something that no one else has done before."

Michael Masi will no longer serve as race director in Formula One as the fallout from the 2021 finale in Abu Dhabi continues.

FIA president Mohammed Ben Sulayem announced on Thursday "an in-depth reform of the organisation of refereeing and race direction" in F1, which was unanimously supported by the teams.

This followed a "detailed analysis" of the Abu Dhabi Grand Prix, where Max Verstappen dramatically beat Lewis Hamilton to the drivers' championship last season.

Verstappen pipped Hamilton in the final lap of the final race, denying his rival a record-breaking eighth title.

However, the Red Bull superstar was only able to stage that late recovery after Masi let the cars between the pair – running first and second but separated by a series of lapped rivals – pass a safety car and allow one lap of racing.

Verstappen, on fresher tyres, prevailed, prompting a protest from Hamilton and Mercedes.

Although that bid failed, there has remained a great deal of discussion around Masi's decision-making, leading to Ben Sulayem unveiling his "new step forward in Formula One refereeing".

The most significant change made by the FIA chief is Masi's removal as race director, to be replaced by two men in Niels Wittich and Eduardo Freitas.

Starting from pre-season testing in Barcelona, the new pair will alternate as race director, assisted by permanent senior advisor Herbie Blash.

However, Masi is not necessarily out entirely, as Ben Sulayem added: "Michael Masi, who accomplished a very challenging job for three years as Formula One race director following Charlie Whiting, will be offered a new position within the FIA."

Other changes include a reassessment of the unlapping procedures that caused such controversy.

"Without the referees, there is no sport," Ben Sulayem said. "Respect and support of the referees is in the essence of the FIA.

"That is why these structural changes are crucial in a context of strong development and the legitimate expectations of drivers, teams, manufacturers, organisers, and of course, the fans.

"I warmly thank all those who contributed to this reform.

"These changes will enable us to start the 2022 Formula One season in the best conditions, and our sport will be even more loved and respected."

Lewis Hamilton appears to be back and ready to chase another Formula One title with Mercedes.

The contentious nature in which Hamilton was denied a record-breaking eighth drivers' championship in 2021 had prompted talk he would quit the sport.

Hamilton was pipped by Max Verstappen in the final seconds of the season-ending Abu Dhabi Grand Prix following a controversial decision from race director Michael Masi to let the cars between the pair – running first and second but separated by a series of lapped rivals – pass a late safety car and allow one lap of racing.

Mercedes team principal Toto Wolff warned it was "not possible" for Hamilton to get over the nature of that result, and little has been heard from the Briton since.

But the former McLaren man ended his social media silence earlier this month when he posted: "I've been gone. Now I'm back!"

And Mercedes' own Twitter posts have now revealed Hamilton is back with the team ahead of the launch of their W13 car.

After sharing a picture of Hamilton with the caption "Year 16", the Silver Arrows uploaded footage of new team-mate George Russell being fitted in his seat.

Hamilton appears in the video and greets Russell, and the team added: "Oh wait, Lewis is in this?" A picture of Hamilton with Russell followed.

Hamilton last year signed a contract that ties him to Mercedes through the 2023 season.

Max Verstappen insists he fully deserved his Formula One world championship triumph and does not believe the achievement has been overshadowed by the ongoing controversy around the title-deciding race.

The 24-year-old clinched his first title by pipping seven-time champion Lewis Hamilton on the final lap of the Abu Dhabi Grand Prix in December.

Hamilton had built up a healthy lead over his Red Bull rival in the season finale, with both men having entered the race level on points, until a controversial late safety car period was followed by Verstappen overtaking the Mercedes driver on the final lap.

Mercedes were furious with how race rules were applied in a safety-car situation and challenged the result, believing Hamilton was unfairly prevented from winning the race and the championship when Verstappen passed him with only a few corners remaining.

The FIA last month announced a "detailed analysis" of the contentious ending has started, with the result of the inquiry to be released before this season's first race in Bahrain on March 20.

Regardless of the verdict reached by the sport's governing body, Verstappen does not believe the controversy detracts from his triumph.

"[The FIA] can't do anything," Verstappen told The Guardian.

Asked if he felt his maiden title triumph has been overshadowed somewhat, the Dutchman replied: "Not at all. I had a very good season and I think I really deserved it. 

"I have been really unlucky as well. People always remember the last race but, if you look at the whole season, the championship should have been decided way earlier."

Verstappen was graciously congratulated by Hamilton following his title-clinching victory in Abu Dhabi, bringing down the curtain on an eventful season that saw both drivers take it in turns to lead the standings.

A low point in the campaign for Verstappen came at the British Grand Prix in July when clashing with Hamilton on the first lap as the home favourite tried to force his way down the inside at Copse Corner.

Verstappen smashed the barriers at 180mph and therefore did not finish the race, with Hamilton finishing first and wildly celebrating his win while his title rival was being examined in hospital.

However, the Red Bull driver did not use that as extra motivation for the second half of the season.

"I don't think we work like that," he said. "It's disrespectful what happened there but we looked at what we could have done better. 

"Once we came back from the break as a team we really did a good job because we won races in the second half of the season we shouldn't have won."

While talk still rumbles on regarding the end of the 2021 season, the new campaign is now just over a month away and Verstappen has a target on his back as defending champion.

"That little pressure in the back of your mind, of having to win a world championship or trying to win it, has gone," he said. 

"It's already happened. I've done it. So when it's tough or you're having bad luck you probably will deal with it easier than normal."

Lewis Hamilton has hinted he may return to Formula One this season in a cryptic post on his social media accounts.

The seven-time world champion's future in the sport is uncertain after he was denied a record-breaking eighth title by Max Verstappen at the end of last season.

Hamilton looked set to surpass Michael Schumacher heading into the final stage of the Abu Dhabi Grand Prix, only for Verstappen to controversially snatch glory in the closing moments.

It is unknown whether the Mercedes driver will return in 2022, with former F1 chief executive Bernie Ecclestone stating his belief that he would retire.

Meanwhile, brother Nicolas confirmed that Hamilton was taking a break from social media – on which he had been quiet having not posted since December 11 – while relaxing with family in the ski slopes.

But the 37-year-old has broken his silence. Addressing his 33.8 million followers across Twitter and Instagram, Hamilton posted: "I've been gone. Now I'm back!"

Should he return, Hamilton is set to partner George Russell at Mercedes in his latest quest for an eighth world title.

Mercedes hope they will be prepared for the 2022 Formula One season, in which technical director James Allison is forecasting "a terribly painful year" for teams who get their car "really badly wrong". 

F1 is belatedly introducing its game-changing new regulations in the coming year, shaking up the sport after an epic 2021 season. 

The 2022 car has been designed with the aim to end the dominance of any one team and ensure closer racing. 

Mercedes, whose Lewis Hamilton was agonisingly pipped to the title by Max Verstappen in the previous campaign, will expect to again be at the forefront of a title tussle, but Allison recognises some outfits will be caught unaware. 

The price for making mistakes this year is a significant one, he believes. 

"Everyone in our team, and everyone in every other team, will have done our level best to try to find a design and an approach that will be a happy match to this new regulation set," Allison said in a video posted by Mercedes. 

"And we'll all get to find out together at the start of this season, in the races that unfold from there, exactly how that shakes out. 

"I would imagine, given that the cars are so new and so different, that one or two cars on the grid will have got it really badly wrong. And they will have a terribly painful year. 

"I would imagine that all of us to some degree will have left things on the table that we just didn't anticipate. And we will look at other cars and think, 'Oh, why didn't we think of that?' 

"Then we'll be scrambling around to try to get that idea onto our car as fast as possible, so that we can claw our way, from whatever position we land in that first race, forwards. Or, if we're lucky enough to be in front, to keep the attacking wolves behind us. 

"It's going to be quite a rush and definitely something that's going to keep us all from having too much sleep for the whole of the season." 

George Russell is joining Hamilton at Mercedes this year, replacing Valtteri Bottas after impressing with Williams. 

A "detailed analysis" of the controversial ending to last month's Abu Dhabi Grand Prix has started, the Federation Internationale de l'Automobile (FIA) has confirmed.

Seven-time champion Lewis Hamilton was denied a record-breaking eighth title when he was beaten by Red Bull's Max Verstappen on the final lap of the season-ending grand prix on December 12.

Mercedes were furious with how race rules were applied in a safety-car situation and challenged the result, believing Hamilton was unfairly prevented from winning the race and the championship when Verstappen passed him with only a few corners remaining.

The German constructors launched two challenges that were both rejected by the FIA, with Mercedes giving notice of an intention to appeal. However, the team eventually decide not to proceed down that route following discussions with F1 and the FIA.

On Thursday, the FIA released a statement via Twitter outlining the next steps in their analysis of the situation, saying: "Following the decision of the World Motor Sport Council in Paris on 15 December 2021, the FIA administration, under the leadership Mohammed Ben Sulayem, has started the detailed analysis of the events of the last Formula 1 Abu Dhabi Grand Prix.

"The FIA President launched a consultation with all F1 teams on various issues, including this one.

"On January 19, an item on the agenda of the Sporting Advisory Committee will be dedicated to the use of the Safety Car. The following stage will be a shared discussion with all F1 drivers.

"The outcome of the detailed analysis will be presented to the F1 Commission in February and final decisions will be announced at the World Motor Sport Council in Bahrain on 18 March."

There has been recent speculation since the end of the season that Hamilton could retire from motor racing, with the 36-year-old and his team left distraught by the outcome, and reports suggest that the Briton is waiting to see the outcome of an inquiry.