Formed by Hammers supporters Jack Elderton and Callum Goodall to offer their fellow fans in-depth but accessible analysis of their team and its players, Analytics United use performance analysis and data to examine how today’s London derby could play out...
After another tumultuous season in West London concluded with a sixth-placed finish in the Premier League, a semi-final defeat by Manchester City in the FA Cup, and a set of runners-up medals in the Carabao Cup, Chelsea’s new hierarchy decided to call it quits with former Spurs manager Mauricio Pochettino at the end of last season. The Argentine had managed to get Chelsea performing at a much-improved level during the run-in but it wasn’t enough to convince his bosses against moving for up and coming Italian manager Enzo Maresca off the back of his promotion-winning season with Leicester City in the EFL Championship.
Maresca’s Leicester side finished up with 97 points, 89 goals scored, and a fantastic looking xG difference of +0.92 and the former West Bromwich Albion midfielder and West Ham United coach has been tasked with establishing a structure that better enables control with consistency, something more befitting of a club intent on challenging on all fronts and competing again in Europe’s premier club competition, the UEFA Champions League.
In order for Chelsea to return to those levels, Maresca will need to have a huge positive impact from the very beginning and whilst results may be yet to convince – the Blues lost to Manchester City on the opening weekend before falling to defeat in the second leg of their UEFA Conference League play-off with Servette and drawing with Oliver Glasner’s Crystal Palace – things do look a lot more positive for Chelsea when comparing last season’s data with the early numbers so far.
Of course, with just three games played at the time of writing, it is far too early to draw any clear conclusions, but there have been significant positive jumps in some of the data associated with Chelsea’s in-possession play. The Blues were significantly above average for the percentage of total touches they took in the defensive third last season, 33.8%, indicating that they frequently circulated the ball in their own third of the pitch. But this season, they’re averaging just under 30%, taking them from near-average to towards the bottom quarter of teams across Europe’s top five leagues, suggesting that although Maresca is still keen for his team to hold on to possession, he’d like to see them do so higher up the pitch. Consequently, there has been an upturn in the percentage of touches Chelsea take in the midfield third, rising from 43.5% up to 46.1%, an increase that takes them from well below the European average last season to well-above the average in the current campaign.
In a similar vein, Maresca has also improved how frequently his team can pass the ball into their opposition's third. As their possession was more commonly in deeper areas last season, passes into the final third were generally the responsibility of Chelsea’s midfielders, Moisés Caicedo and Enzo Fernández. However, with Maresca adjusting the team structure and enabling Chelsea’s backline to operate on the halfway line more frequently, the data shows us that the responsibility for passing into the final third is now being shared around the squad. Last season, only Caicedo, Fernández and Cole Palmer were averaging over 4.5 passes into the final third per game but defensive duo Marc Cucurella and Wesley Fofana have now joined them. This has led to improvements all round, where Chelsea are averaging almost five more passes into the final third per match, allowing them to pin teams back in their own defensive third.
It would be remiss of us not to mention the creative prowess of Palmer, who has taken on increased responsibility under Maresca whilst maintaining his high levels of attacking output. He returned 22 goals and eleven assists last season, and his 2024/25 campaign has begun in a similarly productive manner with one goal and four assists over his first three outings. The ex-Manchester City man spent most of last season playing off the right wing, but his new manager has moved him into the centre of the pitch and encouraged him to exert his influence on earlier phases of play. When Chelsea are building up from the halfway line, he can be seen dropping into deep midfield, looking to get on the ball and push the team forward. Under Pochettino, this was often Fernández’s responsibility, but his progressive passing data has dropped off, with Palmer emerging as the leading progressor. He’s currently averaging 6.9 progressive passes per 90 whilst maintaining his impressive creative numbers. If the Hammers want to cause Maresca’s men problems, Lopetegui will have to devise a solution to limit Palmer's influence on the game.
Despite those improvements and a change of approach that should bring about greater stability through repeatability, things don’t look so good on some of the key defensive metrics. A possible hangover from the last campaign, Chelsea have continued to struggle to protect the 18-yard box across the opening games of the 2024/25 campaign. They continue to rank in the worst-performing 15% of teams for allowing opposition touches in the penalty area and seemingly struggle in particular with players who carry towards their box.
Among their defensive players, only Fernández and Caicedo are tackling dribblers with more than 50% success, with the fullbacks averaging just 32%. Resultantly, the Blues rank in the worst 11% of teams across Europe's top five leagues for allowing opponents to carry into the box, a stat that places them alongside newly promoted teams Leicester City and Southampton. This weakness is something that Lopetegui will be keen to target as he prepares his West Ham United squad, using the ability of players like Mohammed Kudus, Jarrod Bowen, and Crysenscio Summerville to attack Chelsea’s box.
Another area where Chelsea have struggled so far this season is in the air. When looking at the team that has started most of the games so far, this isn’t particularly surprising as there are only four six foot-plus outfielders with Cole Palmer the tallest ahead of Levi Colwill, Fofana, and Nicolas Jackson. Fofana has only managed to win one aerial duel at the back so far and perhaps Tomáš Souček could be brought back in to exploit this pressure point. The Czech midfielder has clocked up 1.2 non-penalty expected goals across his two starts, giving him the highest per 90 rate of any midfielder in the league so far this season and making him a fine asset to turn to when set-pieces and long balls look like promising routes for chance creation.
This will be a difficult game as Chelsea seem to be turning a corner under their new manager but if Lopetegui’s side can find a way to control Palmer, cope with the attacking overloads Chelsea bring into play, and find their best quality on both counter-attacks and set-pieces, the Spaniard’s side are more than capable of taking all three points and a huge confidence boost away from this match.
*The views and opinions expressed in this article are those of Analytics United and do not necessarily reflect the views and opinions of West Ham United.
