A game-changing appearance off the bench from Cole Palmer and a fine strike from Moises Caicedo were not enough for Chelsea to reclaim top spot in the Premier League as they conceded from a late long throw to draw 2-2 away at Brentford.

Enzo Maresca made three substitutions at the break such was Chelsea’s first-half display: at that point they trailed 1-0 after Kevin Schade ran onto a fine 40-yard pass from Jordan Henderson and finished.

Little changed though until Palmer came of the bench for Jamie Gittens on 56 minutes and five minutes later he had scored, sweeping in Joao Pedro’s knockdown for his first Premier League goal from open play since January.

Palmer has been sidelined since before last month’s West Ham United game with a groin injury but looked sharp on his return and could have had a second when Caoimhin Kelleher blocked his attempt from Pedro Neto’s cutback.

Caicedo looked to have won it with a fine strike from the edge of the box but Fabio Carvalho got on the end of a long throw in the 93rd minute to level it.

Here The Athletic’s Cerys Jones analyses the game.

How did Palmer change the game?

Maresca gave his changes ten minutes after half-time before deciding Chelsea needed some X-factor, some dynamism… some Cole Palmer.

Five minutes after his introduction, he had the ball in the back of the net.

Palmer’s neat first-time finish from Joao Pedro’s flicked header, while preventable with some more vigilant defending, demonstrated the box threat his side had been missing.

His urgency, though, was what particularly stood out. He made several promising off-ball runs into the right channel and howled in frustration when Enzo Fernandez did not spot one of them. His words in the referee’s ear also look to have contributed to Ethan Pinnock’s 82nd-minute booking for taking his time over a throw-in.

When Palmer came on, he dragged his side from scrabbling for an equaliser to driving for a win. He was also key in the build-up to Caicedo’s goal that looked to have won it.

After missing the international break, Palmer needed little time to refresh watching England manager Thomas Tuchel’s memory of his quality.

How did Caicedo’s night change?

A striking difference between Chelsea’s two halves was not a substitute, but someone who stayed on the pitch throughout. Caicedo’s thunderbolt goal stood in sharp contrast to the suffocated, frustrated figure he cut in the first half.

Before the break, Brentford forward Thiago’s unglamorous but successful role was simply to man-mark the Chelsea playmaker out of the game. He did so effectively enough that, despite Brentford not pressing Chelsea’s back line, the away side’s build-up was completely suffocated.

Their efforts to replace that controlled, possession-based play through the middle with using quality and pace on the wingers did not pay off, with Gittens and Neto both struggling physically against the Brentford full-backs.

Moises Caicedo celebrates with Alejandro Garnacho (Henry Nicholls/AFP via Getty Images)

The second half was a different story. With more dynamism in Chelsea’s midfield after Reece James and Marc Cucurella were introduced, a rigid man-marker on Caicedo was no longer as easy to accommodate and he found some breathing room. In the 85th minute, he drifted free of Schade, took the touches he had not had room for in the first half, and rocketed the ball home.

Why did Maresca change three players at half-time?

Chelsea handed debuts to Facundo Buonanotte and young defender Jorrel Hato, presumably with one eye on their approaching Champions League opener against Bayern Munich. Buonanotte played as a No 10 in behind Joao Pedro up top, while Hato was tasked with replacing Cucurella at left-back. Wesley Fofana also came in for James at right-back.

Hato’s inexperience with Maresca’s system showed, with him lacking Cucurella’s mobility and the positional awareness to effectively support Gittens in attack and recover defensively. The ‘Cucurella role’ is one he is not yet accustomed to, and it showed. The Spanish full-back came on at half-time and slotted in with ease. James, who replaced Fofana, was much more comfortable rotating into midfield and driving forward with the ball.

It was a much-improved defence — right up until the third minute of stoppage time. A moment of naivety, and the inability to physically dominate the box, let Chelsea down and allowed Carvalho to ghost in at the back post and turn home Kristoffer Ajer’s header.

Fabio Carvalho scores a late equaliser (Crystal Pix/MB Media/Getty Images)

The final change, with Tyrique George replacing Buonanotte, saw an attacking shift with George leading the line and Joao Pedro dropping into the No 10 position. In the first half, the Brazilian had looked frustrated at his lack of service up top and popped up all over the pitch as he sought to get on the ball.

His creative efforts were welcome, but left Chelsea lacking a focal point up top — something Maresca moved to address at half-time. It leaves a question mark over whether Joao Pedro is best suited to fill in as centre-forward while Liam Delap is injured, though the Brazilian moved back up and George moved left when Palmer was introduced to play as No 10.

Marc Guiu’s omission from the matchday squad, despite his being recalled from a loan at Sunderland after Delap’s injury, also raises questions about his position in the  pecking order.

What next for Chelsea?

Wednesday, September 17: Bayern Munich (away), Champions League 8pm UK, 3pm ET

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