It is safe to say few people at Chelsea predicted this season would end with Marc Cucurella performing a turn as an inverted full-back. As one figure inside Stamford Bridge put it recently, who could have imagined that a Cucurella revival would be one of the key reasons behind Mauricio Pochettino’s team making a late surge for European football?

Let’s roll this back. In August 2022, with the new order at Chelsea still asserting itself, Cucurella was invited to Mykonos to meet the interim sporting director. Todd Boehly, it turned out, was a man who knew how to conduct a charm offensive.

The American had seen Manchester City fail to meet Brighton’s asking price for the left-back. A window of opportunity emerged. Chelsea’s scouts were long-time admirers of Cucurella.

Boehly, keen to do the deal, agreed to pay. Brighton, who bought Cucurella for £15.4m in 2021, were somehow convinced to sell him for £55m plus £7m in add-ons, a deal that left many wondering whether Chelsea’s owners were perhaps getting a little bit too giddy in the transfer market.

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“He’s a good player,” a Spanish source said at the time. “He’s just not a £60m player.” And sure enough, before long Cucurella was finding it difficult to live up to his fee.

He struggled with injury and illness, his performances were sketchy and he soon became a scapegoat for frustrated supporters, who booed the Spain international when he came off the bench during Chelsea’s first-leg defeat by Borussia Dortmund in the Champions League last season.

Here we had it: one of the most pertinent examples of Chelsea’s wild, destructive overspending. Cucurella was a joke, a flop, maybe even a hate figure. Fans winced if they saw him in the starting XI.

They saw a defender who couldn’t defend. They saw little evidence of the full-back who had given Brighton so much in possession. They were disappointed when Manchester United decided not to sign Cucurella on loan last summer.

Pochettino, though, has refused to give up on the 25-year-old. The vibe has changed since Cucurella suffered in a back three when Graham Potter’s Chelsea were hammered 4-1 by Brighton last season. He is in a much better place before returning to the Amex Stadium to face his old club on Wednesday evening.

There is clearly a defiant streak to Cucurella. He delivered a tenacious performance as a right-back when Chelsea played Brighton in the Carabao Cup this season. Predictions about Cucurella being ripped apart by Kaoru Mitoma were wide of the mark. Cucurella, who also had a good game against Bukayo Saka in October, snapped into challenges and kept the dangerous Japan winger quiet.

Admittedly there have been times when Pochettino has been reluctant to trust him. He used Levi Colwill, the young centre-back, on the left during the first half of the season and no one seemed particularly bothered when Cucurella was ruled out for three months after ankle surgery in December. His return to action in March hardly seemed cause for celebration.

But something changed. Last month, with Chelsea 2-0 down at half-time to Aston Villa, the situation seemed terminal for Pochettino. His team had just lost their FA Cup semi-final to City and been thrashed 5-0 at Arsenal. Another humiliation was on the cards when Cucurella scored an early own goal against Villa. Then, thanks to a little tactical tweak from Pochettino, the comeback began.

Cucurella’s role was pivotal. Finding the right formula in midfield has been a challenge for Chelsea all season. There was rarely any balance when their £222m duo, Moisés Caicedo and Enzo Fernández, played together. Caicedo was too often left exposed by Fernández, whose physical shortcomings were exacerbated by playing through the pain of a hernia problem for six months.

It was better once Fernández had surgery and the energetic Conor Gallagher moved back to play alongside Caicedo, who has gone from strength to strength in recent weeks. Yet the real trick was shifting Cucurella inside, giving Chelsea an overload in midfield. Villa couldn’t handle it. They didn’t know how to combat Cucurella, whose positioning allowed Chelsea to dominate and draw 2-2.

It has since been asked why Pochettino took so long to reposition Cucurella. After crushing wins over Tottenham and West Ham, though, he pointed out that he has had to build slowly.

“You cannot sit if you don’t have a chair,” Chelsea’s head coach said. “It’s like an engineer who is going to build a building, who says: ‘I want to see so quickly the nice furniture and the flat.’ First of all, we need to build the structure.”

It is a fair point. Cucurella, who came through Barcelona’s academy, is technically gifted enough to make the system work. Yet it is a work in progress. Last Saturday, Nottingham Forest neutralised Cucurella by creating a blockage in the middle.

Even so, the fact that opponents are having to counter Pochettino’s gameplans is a good sign. But for Cucurella, this is more than a mere tactical story. It is also a tale of resilience. Fans were singing his name – in a good way – during the 5-0 win over West Ham. Against the odds Cucurella, a slightly eccentric figure on the pitch, has become a cult figure. He has done it the hard way.