Inside Chelsea's epic Premier League turnaround 

Chelsea's rise under new coach Enzo Maresca is staggering, and much of the credit has gone to the team's headlining attackers, England's Cole Palmer and Senegal's Nicolas Jackson. The two have played fantastically, tallying a combined 19 goals and nine assists

But Palmer and Jackson aren't the masterminds behind Chelsea's improvement. They are on track to mirror their 2023-24 season statistics. They've been this good for years — it's the rest of the team that has improved around them.

But who has improved the most? With Maresca leveraging the same 4-2-3-1 formation championed by his predecessor, Mauricio Pochettino, it's not that hard to find them.

Marc Cucurella | Left Back

Cucurella is a talented defender, but he didn't always show it under Pochettino. The reason was poor positioning. Pochettino played Cucurella as an inverted fullback and tasked him to play on the right wing rather than the left. 

There are many reasons why he might've done so — Pochettino is a big believer in "ocular dominance" and plays athletes out of position to take advantage of it — but it left Cucurella vulnerable all season.

Maresca wasn't having any of that. He'd seen Cucurella thrive on the left side while playing for the Spanish national team and uses him there instead. The results of that change have been overwhelmingly positive: Cucurella is much more comfortable moving forward from the left side. He has made 15.8% more midfield touches and passes per game this season than he did in 2023-24.

Jadon Sancho | Winger

Sancho arrived from Manchester United just before the start of this season, puzzling media. Chelsea already had a left winger on its roster, Ukrainian youth prospect Mykhailo Mudryk, who arrived in 2023 on an 8 1/2-year contract.

Maresca knew the uncomfortable truth that Mudryk was a poor investment and couldn't lead Chelsea to new heights. He dropped Mudryk for Sancho, and the results speak for themselves. Sancho has posted 28% more goals, 400% more assists, 100% more progressive upfield passes and a 25% better pass completion rate than Mudryk did on a per-game basis.

Romeo Lavia | Midfield

Lavia spent much of 2023-24 injured, and his absence hurt Chelsea more than it realized at the time. Pochettino played Ecuadorian utility player Moises Caicedo in Lavia's place, and while Caicedo was fine, he certainly wasn't spectacular. 

Lavia is. He's a much better defensive player than Caicedo, and that's precisely what Chelsea needed from that deep midfield position. Lavia has made 80% more interceptions and 20% more tackles than Caicedo on a per-game basis. He also has won 37% more of his take-ons than Caicedo did.

But Lavia doesn't just excel defensively. He also makes Enzo Fernandez, his midfield partner at the base of Chelsea's 4-2-3-1, stronger, too. Fernandez had made 133% more goals and 221% more goal-creating actions per game with Lavia than he did with Caicedo. That's Lavia's defensive strength coming to fruition. Now Fernandez can roam farther forward when he knows Lavia is there to cover for him.

Chelsea's Premier League season will continue Sunday at home against Brentford. Then Chelsea will enter the busy holiday season, playing four Premier League matches in 14 days. If it comes out of those matches against Everton, Fulham, Ipswich and Palace with a solid points haul, it will cement its place in the Premier League top four.