For Real Betis, the past 15 years haven't been the easiest. They've been relegated from LaLiga twice and failed to secure a first return to the Champions League since 2004-05, while just a few kilometres north, their bitter rivals Sevilla have enjoyed the greatest period in their existence.

Sevilla have won six UEFA Cup/Europa League titles, a couple of Copa del Rey crowns, the European Super Cup and qualified for the Champions League eight times.

Back in January 2018, the winds of change appeared to sweep through Seville. Betis were 5-3 winners at the Ramon Sanchez Pizjuan in an astonishing, historic match.

Sevilla hadn't lost any of their previous 29 home matches, a run that stretched back to 2016, and were unbeaten in eight editions of Spain's fiercest derby. But on the day, Quique Setien's men were as irresistible going forward as the hosts were hopeless at the back.

Betis went on to finish sixth in the table, one place above a Sevilla side that went through three coaches over the course of the season. It was their first campaign without famed sporting director Monchi and without him they struggled massively for direction.

This was arguably the most vulnerable their status among Spain's top clubs had been since returning to LaLiga in 2001-02, yet they largely managed to weather the storm and Monchi's return restored much-needed stability. Betis, on the other hand, finished 10th and 15th in the following two campaigns, the promising early work of Setien proving something of a false dawn.

But once again there is an aura about Betis, and success in Sunday's Gran Derbi would really show they mean business.

Fun but flawed

Manuel Pellegrini's reputation in some quarters may have taken a bit of a bashing after a fairly underwhelming spell at West Ham, but it was going to take something drastic for him to be written off in Spain given the miracles he worked at Villarreal earlier this century.

It's fair to say things have gone well at the Benito Villamarin for the Chilean, with their sixth-placed finish in 2020-21 ensuring a return to the Europa League and they've started 2021-22 in fine fashion as well.

In fact, their record in 2021 is especially startling. They have lost just six of 42 matches across all competitions this year – across the top five European leagues, only Inter have been defeated less often.

While this Betis may not provide quite the same thrill ride as Setien's from a few years back, they're certainly among LaLiga's greatest entertainers this season.

The personnel available to Pellegrini gives Betis the technical capability to knock the ball around well but they're arguably at their most comfortable when getting the ball forward quickly, with their 26 direct attacks second only to Real Madrid (28) this season.

This coupled with the high quality of the individuals they possess in attack makes them one of the more threatening teams going forward, with their 13.0 expected goals (xG) from open play only bettered by Madrid (15.5), Barcelona (14.7) and – fractionally – Sevilla (13.1).

They are also efficient pressers. While their 79 high turnovers may only be the seventh highest in LaLiga this term, their 24 shots from such situations is at least four more than anyone else – these haven't led to any goals yet, but it's a positive sign that they appear pick their moments to increase the pressure well.

But conversely, one of the other reasons that Betis matches are so entertaining to watch is that they're not particularly solid at the back, as Thursday's 4-0 Europa League hammering by Bayer Leverkusen showed.

Now, this can potentially be explained by their attack-first mentality, but it should be a cause for concern in the long run if they cannot fix it, especially if they do harbour hopes of finishing in the top four.

Their 11.8 expected goals against (xGA) in open play is the third-worst in LaLiga and almost double Sevilla's respective record (6.2), and that probably doesn't bode well for a derby that can be open and frantic.

The Leverkusen loss came just a few days after Betis were also particularly poor defensively against Atletico Madrid, a 3-0 defeat in which they barely laid a glove on the defending champions.

And perhaps therein lies the biggest psychological barrier of all ahead of Sevilla's visit. Under Pellegrini, Betis have won none and lost seven of their 10 matches against their neighbours, Madrid, Atletico and Barca.

A win on Sunday will move them level on 24 points with Sevilla, who head into the weekend only a point off the top, but arguably more important than anything is that defeating Julen Lopetegui's men might finally show they can rise to the challenge of the league's best teams.

Beauty and the beast

When on song, there are few players in LaLiga more thrilling to watch than Nabil Fekir. Betis fans probably pinch themselves that he's still at the Benito Villamarin – to be honest, the very fact they managed to sign him in the first place was pretty remarkable.

Ignoring the petulance that saw him sent off in Leverkusen, Fekir's made a very lively start to 2021-22, which made it even more astonishing that Pellegrini opted to rest him against Atletico. Now, he was only one booking away from a suspension that would've ruled him out of the derby, but still.

Of course, his talents are nothing new to many, but he's proving what an asset he is with his form at the moment.

His 33 chances created is the second-most in LaLiga after Iker Muniain's (39), with the Frenchman both effective in open play and set-pieces, with these opportunities amounting to 2.7 expected assists, second only to Memphis Depay (4.5).

In open play is when Fekir's at his most useful for Betis, though, with his exceptional close control and dribbling skills able to open up spaces and situations that others can't. He's completed 29 dribbles this term – Javi Galan (30), Yannick Carrasco (31) and Vinicius Junior (33) are the three with more.

He's also attempted the third-most shots (34) in the league, though his one-goal haul (2.1 xG) suggests he might be better off showing a little more restraint.

But while Betis are undoubtedly a side that's easy on the eye with the likes of Fekir and Sergio Canales on the pitch, they've also got someone adept at doing the dirty work.

Guido Rodriguez has enjoyed a rapid rise to prominence since moving from Club America in January last year, with the Argentina international's trademark bite and tenacity quickly becoming a key element for Betis.

A tall and strong defensive midfielder, Rodriguez has great presence without the ball. Even if he doesn't necessarily win the ball back himself, his willingness to get stuck in gives Betis real steel in the middle and makes him a formidable opponent.

He may not possess the passing ability of William Carvalho, but he's a considerably greater defensive presence, with Rodriguez averaging 3.1 tackle attempts per 90 minutes since the start of last season – among players to play at least 1,000 minutes in that time, only two players have been more forceful than him.

He also ranks in the top 10 among the same players for possession won (7.7) each match. There really is more to Betis than just the craftiness of Fekir.

Sevilla lacking soul

Betis' midfield could be the key on Sunday. While it's in this area of the pitch with players like Rodriguez and Fekir that they thrive, midfield is probably Sevilla's weakest area.

While Fernando was excellent for much of last season and Joan Jordan was solid enough as a No.8 a little in front, Lopetegui muddled through the campaign without ever really figuring out what to do with that third – the most advanced – midfield position.

Ivan Rakitic was usually the one to play there, but Oscar Rodriguez, Papu Gomez and Oliver Torres were also all used there to minimal success. But while that didn't really look like much of a problem last season, there's been little to suggest Lopetegui's fixed the issue, and it's been exacerbated by Jordan going through a drip – the Spaniard has seemed less influential, with his touches dropping from 88.1 each game to 74.4.

Lopetegui has come under fire from some supporters this season for the football they've played, which has looked especially monotonous in the Champions League, but let's not forget they could feasibly go into the international break top of the table, and they do have their strengths.

They may not engage in exhilarating high pressing, with their 46 high turnovers comfortably (by 10) the lowest in the division, but with the likes of Jules Kounde and Diego Carlos, Sevilla are pretty adept at evade their opponent's attempts to press, as evidenced by the fact their 66 high turnovers against is the fourth-lowest.

Similarly, while their forward line may not trigger a high press, once their opponents get into midfield, they are extremely persistent. There have only been four instances of teams managing to string together 10 or more passes that lead to either a shot or touch in the box against Sevilla, the best such record in the division.

But in possession, this is a Sevilla side that lacks identity. While they like to dominate the ball, with their 6,011 passes this season third to Barcelona (6,899) and Madrid (6,173), they're hardly masters of 'tiki-taka'.

Their 40 sequences of 10 or more passes is the third-highest in LaLiga, but they've yet to score a goal in that manner. When they go direct, they're far more efficient, with 13 – which is below average in itself – direct attacks yielding three goals.

It could be argued that the playmaker they're missing is all that's preventing Lopetegui turning Sevilla into a truly excellent team.

Betis will hope something doesn't suddenly click this weekend as they look to overcome a significant mental barrier.