Chelsea are the Premier League’s most fun team but is it sustainable?

Watching Chelsea this season ought to come with a health warning. Goals arrive in abundance, leads are established before spectators have settled into their seats and clean sheets have become an alien concept. Xabi Alonso has transformed Chelsea into one of the Premier League’s most thrilling spectacles. They have scored 15 goals and conceded 13. That’s 4.7 goals per game in six matches. Chelsea are a neutral’s dream, but is it sustainable?They have scored 15 goals from an expected goals total of just 8.4, an over-performance of 6.6. An 18.3% conversion rate is second only to Manchester City’s 19.1%, while eight of their 15 goals have come from shots with xG below 0.13. The five goals against Bournemouth last weekend came from an xG of just 0.75.Cole Palmer, João Pedro and Morgan Rogers complement each other’s qualities. Palmer’s instinct to drift into pockets of space and dictate attacks gives Chelsea a creative focal point; Rogers provides the direct running and ball-carrying to unsettle defences; and João Pedro offers the movement to stretch opponents in behind and the composure to finish when chances arrive. They rotate roles too, giving defenders a constant headache – they can’t crowd out one of the trio without giving another space.Their forwards deserve credit for their clinical finishing but Chelsea’s attacking numbers will surely revert to the mean at some point, so they need to improve defensively. They have conceded 13 goals, the joint most in the league, and have not kept a clean sheet in the Premier League since January – a run of 22 games. It is a far more volatile position than a serious European contender would want. Alonso’s structure is built to commit players forward; that high-risk, high-reward approach helped his Bayer Leverkusen team win the Bundesliga but Chelsea are not yet set up to protect against the risk.When they are in possession, both wing-backs, their two attacking midfielders and João Pedro push on. That leaves the back three and two midfielders covering, and one of the central pair often gets pulled forward too. The result is that they lack the protection to deal with turnovers. The midfield is left covering a huge area, the wing-backs leave space in behind, and the back three are left scrambling to defend the gaps.Chelsea’s 3-0 defeat by Brentford before the international break was a wake-up call for Alonso. Andrews’ side repeatedly targeted the space behind Chelsea’s advanced wing-backs, forcing the midfield to choose between tracking runners out wide and exposing the centre, or holding position and allowing Brentford to progress down the flanks. All three goals exposed Chelsea’s defensive vulnerabilities: the first followed a corner won through pressure down the flank; the second saw Kevin Schade break behind Chelsea’s defence before Thiago converted the rebound; and the third came after Schade was given time and space out wide to cross for a back-post finish.As Chelsea pushed forward in search of a response, the defence became increasingly stretched. It exposed the central dilemma in Alonso’s system: committing players forward increases their attacking threat but leaves space for opponents to exploit.The good news for Chelsea fans is that there were encouraging signs in their 5-1 victory over Bournemouth that suggest Alonso used the long international break to find a solution. On first inspection it had all the hallmarks of a standard Chelsea game this season: a two-goal lead inside three minutes, ruthless finishing that defied the xG statistics, a six-goal thriller, and no clean sheet. But look a little deeper and it appears Chelsea may be beginning to find a better balance.The most significant change was a move to a 4-4-2 shape out of possession, defending in a back four rather than a back three. Josh Acheampong played more like a right-back; Levi Colwill and Maxence Lacroix moved closer together; and Pep Chavarría held back on the left while Neto pushed on the right.They defended with a more recognisable shape, and the space between the lines was more manageable. The return of Moisés Caicedo was another boost. It provided the team with a vital source of energy, ball-winning and protection in front of the defence – he won seven duels, made the joint-most tackles in the game (four), and the second most defensive contributions (11). Jordan Henderson brought leadership and organisation to the midfield, organising the press with regimented efficiency.Moisés Caicedo’s return from injury made a big difference for Chelsea against Bournemouth. Photograph: David Cliff/EPAIt was by no means a complete solution; they still committed players forward and took risks. Bournemouth managed to exploit lapses and find space behind a number of times; they had 67 entries into Chelsea’s final third compared with Chelsea’s 39. Alonso’s next goal will be to develop a shared understanding among the players. They need to recognise the same triggers, move at the right moment and trust their teammates to cover the spaces they leave behind.Chelsea are perhaps the Premier League’s most entertaining side, but entertainment does not secure European football. Their finishing is unlikely to stay this ruthless so the defence needs to step up. The performance against Bournemouth offered encouraging evidence that the defence can improve their organisation without sacrificing their threat going forward, and the return of Caicedo gives the midfield the legs and authority it has lacked. If Alonso can turn these positive signs into consistency, Chelsea may become a side capable of thrilling their supporters without putting them through quite so much stress.This is an article by WhoScored