If Thomas Tuchel is after any advice on how to deal with the Romelu Lukaku issue, the Chelsea head coach could do worse than to have a brief word with the man he will come face-to-face with on Wednesday.
Under now-Tottenham boss Antonio Conte across two seasons with Inter, Lukaku enjoyed the best form of his career, scoring and assisting a combined 81 goals in 95 appearances.
Lukaku has not been as prolific since returning to Stamford Bridge in August, finding the net seven times in 18 games, and already his future at Chelsea has been called into question following an explosive interview in the Italian press that was published last week.
The Belgium international was subsequently dropped for Chelsea's crucial clash with Liverpool on Sunday but is in line return for the EFL Cup semi-final first leg with Spurs after holding clear-the-air talks with his manager, meaning a possible reunion with Conte.
Here, Stats Perform looks at how Conte got Lukaku out of the "deep hole" he found himself in at Manchester United, as the striker himself put it, and explores how Tuchel can go about getting the most out of Chelsea's all-time record purchase.
ROM AMONG EUROPE'S ELITE
As well as declaring an unhappiness with his role at Chelsea and expressing a desire to return to Inter as part of his 30-minute chat with Sky Sport Italia, Lukaku also opened up on the "hurt" he felt when Conte departed San Siro.
That is no surprise given the Belgian's form between arriving at Inter in August 2019 and departing two years later.
The 47 Serie A goals scored by Lukaku in 72 games under Conte is his best return under any of the 11 managers he has played for at club level, followed by the 43 netted in 103 Premier League games when working with now-national team coach Roberto Martinez at Everton.
That includes a return of 24 goals in 2020-21 alone, on top of 11 assists, as he became the first player to score 20-plus goals and set up 10 or more in a single Serie A season since Opta started to record such data in 2004-05.
Indeed, only Cristiano Ronaldo (83), Kylian Mbappe (97), Lionel Messi (106) and Robert Lewandowski (121) were directly involved in more goals in all competitions among players from Europe's top five leagues than Lukaku's 81 across the 2019-20 and 2020-21 seasons.
FLOPPED IN FAVOURED FORMATION
That impressive form helped Inter end their 11-year wait for Scudetto success last time out, a year on from falling just short in the Europa League with defeat in the final, but Lukaku was not alone in inspiring the Nerazzurri to glory.
Alongside him was Lautaro Martinez, who was very much the perfect foil in Conte's preferred 3-5-2 formation, which the Italian used 31 times in 38 league matches last season.
It is a formation Tuchel has used on only two occasions in the Premier League this term – in September's 1-0 home defeat to Manchester City and the 1-0 victory at Brentford three weeks later.
Lukaku started both games alongside Timo Werner and Chelsea's tally of five shots against City and five against Brentford are the fewest the Blues have managed in any league game this term – Lukaku responsible for just one of those – as were the four and two chances created respectively.
While City's quality and dominance of the ball must be factored in, Lukaku's minimal involvement against Brentford was surprising – and surely no coincidence.
That west London derby blank came in the midst of a 10-game run without a goal for Lukaku, not helped by niggling injuries and a COVID lay-off, which he has since put an end to with three goals in four matches.
Chelsea's formation in those three most recent games Lukaku has scored in, incidentally, came with three attackers spread across the frontline. And there was one other common denominator, too: Mason Mount being on the field.
MOUNT TO PLAY THE MARTINEZ ROLE?
Mount assisted Lukaku's most recent goal in a 1-1 draw against Brighton and Hove Albion from a corner and the pair have combined to create nine chances in total for one another in the league this term, making it easily Chelsea's most dangerous partnership.
No Chelsea player has combined more regularly with Lukaku than Mount, with the pair linking up 10.06 times per 90 minutes so far this season. While that may not appear a huge amount on the face of it, next on that list is Mateo Kovacic with 6.45 combined passes between himself and Lukaku per 90.
However, Mount still has some way to go if he is to match the 54 combined chances created for each other in Serie A by Lukaku and Martinez in their two seasons used in tandem at Inter, which equated to nine assists.
Lukaku's relationship with Mount does provide some promise, though, as does the Anderlecht academy product's goalscoring performances in his most recent two outings prior to being dropped against Liverpool, showing Chelsea do not necessarily have to replicate Inter's system to help their main man thrive.
TUCHEL WILL NOT SHIFT
Lukaku is averaging fewer passes, overall touches and touches in the opposition box this season compared to last, while also shooting less frequently, dribbling less and creating fewer chances for others.
Yet instead of attempting to find the perfect formula and personnel for Lukaku, Tuchel will not shift from his own way of thinking.
"We cannot just play like Inter in the hope that will bring the most out of Lukaku. The system they played not only suited Romelu but also Lautaro Martinez and others. If you don't have five players you can't play five defenders," Tuchel said on the eve of the Tottenham tie.
"It works both ways. It is more about principles of how we play. I feel he is more impatient than anything else. He wants to be involved more, wants more big chances.
"Like with every transfer, you have to accept there is a change of environment, culture, team-mates, playing style, belief. He's not the first player to take time, but even while doing it he was scoring goals."
And maybe Tuchel has a point. After all, for all the talk of Lukaku's struggles and unhappiness, he is scoring at an almost identical rate to Cristiano Ronaldo (0.54 goals per 90 minutes compared to 0.56), and remains one of Europe's most prolific strikers of the past decade.
Now back from injury and a team exile brought on by his own actions, only Lukaku can ensure he avoids falling down another deep hole that he may this time be unable to escape.