As a measure of how badly Wednesday night went for Chelsea nothing summed it up more than Thomas Tuchel blaming his side’s latest shoddy defensive display on the state of the Stamford Bridge turf. “It is a very difficult pitch we have here,” Tuchel said as his thoughts turned to Andreas Christensen setting Arsenal on their way to victory by handing Eddie Nketiah the opening goal with a comical shank.

“It is not to our favour and the ball bounces very, very awkwardly when the ball bounces to Andreas.”

It was certainly a creative way for Chelsea’s manager to explain a third consecutive hammering at home. Privately, though, Tuchel knew Chelsea had lost because they were outplayed and outrun by Arsenal. The German looked at himself and asked questions. Had he picked the right starting XI? Tuchel suspected Arsenal would want it more but he did not adjust his lineup accordingly and was unable to influence the game once it became clear Chelsea were intent on contributing to their own downfall.

Chaos reigned. Arsenal simply ran through Ruben Loftus-Cheek and N’Golo Kanté, who was underpowered in midfield, before discomfiting Chelsea’s back three. The space afforded to Bukayo Saka, Emile Smith Rowe and Martin Ødegaard was astonishing. It was as if Chelsea had never seen Arsenal before and the alarming thing for Tuchel, whose side have conceded 11 goals in three home games, is that this performance did not come out of the blue.

The clumsiness, typified by César Azpilicueta dragging down Saka to concede a needless penalty when Chelsea still had time to score a third equaliser, did not appear out of nowhere; it was there when Brentford and Real Madrid ran riot at Stamford Bridge.

The laxness has infuriated Tuchel and he did not want to pin the collapse against Arsenal on Antonio Rüdiger’s absence. “We conceded seven goals with Toni against Real Madrid and Brentford,” he said. “This is about a team performance.”

Where has the focus gone? Being generous it is fair to wonder if the ownership situation has become a distraction for Chelsea’s players. There were 10,000 empty seats in the home sections on Wednesday, with the club unable to fill the ground because of the government’s sanctions on Roman Abramovich, and it is not making excuses to suggest that Chelsea are crying out for the clarity a takeover will provide.

But these are elite professionals. Their job was to solidify their grip on third place and the issues in the boardroom do not fully explain what is happening on the pitch.

Thomas Tuchel looks unimpressed as he watches his side against Arsenal
Thomas Tuchel looks unimpressed as he watches his side against Arsenal. Photograph: Javier García/Shutterstock

It is clear from Tuchel’s demeanour. These aberrations were nowhere to be seen when Chelsea were racking up the clean sheets en route to winning the Champions League last year. They were compact, controlled and so difficult to break down that they started this season by conceding six goals in their first 14 league games, raising the prospect of a three-way title race with Liverpool and Manchester City.

How times have changed. Inevitably, the focus will fall on Christensen, who is expected to join Barcelona this summer. The Denmark centre-back’s mind already appeared to be at the Camp Nou when he blundered for Nketiah’s first goal and he was lucky to last 45 minutes before Tuchel took him off at half-time for the second time in four matches.

However, the introduction of Thiago Silva for Christensen made no difference. Arsenal had given the lead away twice in the first half but Chelsea kept making mistakes. After 57 minutes Azpilicueta gave the ball to Nuno Tavares, Silva, Kanté and Malang Sarr missed chances to clear and Nketiah made it 3-2 with his second opportunistic finish.

It was a mess. Arsenal had so much room on the break and their fourth goal came when Azpilicueta fouled Saka, who scored from the spot. “We have three ball losses in 10 seconds and then we do a foul when there is not the slightest danger,” Tuchel said. “What do you want me to analyse? There is nothing to analyse.”

Only that is not quite true. When Tuchel looks back at his selection he will ask himself whether he should have used Trevoh Chalobah’s fresh legs at right centre-back. He should look at Azpilicueta’s leggy performance and conclude that Chelsea should allow their 32-year-old captain to join Barcelona.

Chelsea need a rethink. Sarr, who deputised for Rüdiger, was awful in and out of possession. The young French centre-back does not look up to it. Saka tormented him, though Sarr was not the only defender who struggled to contain the Arsenal winger. Marcos Alonso, who has been an unsatisfactory replacement for the injured Ben Chilwell at left wing-back, is suspect defensively and was caught out of position when a slick counterattack led to Saka and Ødegaard creating Smith Rowe’s goal for 2-1.

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Where was the cover? It was too easy for Arsenal. There was no pressing from the front from Romelu Lukaku, who was terrible after being handed his first league start since 19 February. The malaise was everywhere. Édouard Mendy did not inspire confidence in goal and it seems that Chelsea are lost in midfield when Mateo Kovacic is unavailable. Jorginho is woefully out of form and it might be a while before Tuchel uses a combination of Kanté and Loftus-Cheek again given they also started together against Brentford.

A different approach is required. Chelsea’s defensive vulnerabilities cost them in their Champions League quarter-final against Madrid and there is a danger of being dragged into the top-four race with Arsenal and Tottenham. The warning signs are clear. Tuchel has to respond. He knows it is not about quality of the pitch.