The Blues were pegged back by Arsenal after Cole Palmer and Mykhailo Mudryk’s first Stamford Bridge goals had put us in a commanding position.
Palmer, leading a fluid Chelsea frontline, coolly converted a 15th-minute penalty awarded for handball, crowning a fast start from Mauricio Pochettino's men.
He went close to adding another before Mudryk did just that in the early throes of the second half, looping a wide effort over David Raya in the Arsenal goal.
We were good value for our lead and didn’t look like losing it until an error at the back allowed Declan Rice and Arsenal a lifeline.
Leandro Trossard completed the comeback with seven minutes remaining, leaving the Blues frustrated despite putting in a good performance.
Malo Gusto returned to the starting XI after his suspension, and Mudryk was selected in attack with Nicolas Jackson only fit enough to be named on the bench, alongside the returning Reece James and Benoit Badiashile.
Marc Cucurella retained his place in defence but at left-back, so Levi Colwill moved infield to join Thiago Silva. Axel Disasi was a substitute for the first time this season.
At a sodden and noisy Stamford Bridge, Chelsea started fast. We hunted in packs to win possession back and from one such break, won the penalty that put us in front. Raheem Sterling’s right-wing cross was met by Mudryk. His header was blocked on its path to goal by the raised hand of William Saliba, so there was no surprise VAR intervened and the referee changed his original decision.
Palmer stepped up and for the second game running sent the opposition keeper the wrong way to give us a deserved lead.
Arsenal did settle thereafter but without posing much of the threat in the final third. The best chance before half-time fell our way, Palmer shooting a whisker wide following super work in midfield by outstanding Gallagher.
It was captain Conor who set up our second three minutes after the restart, although this was an assist in name only! He pounced on a misplaced Arsenal pass and worked it to Mudryk in a wide left position. Misha advanced, looked up and whipped the ball over David Raya’s head and into the far corner. Whether he meant it or not didn’t matter, for Mudryk had his first on home soil! How the Matthew Harding Stand celebrated with him.
Arsenal tried to hit back but fortress Thiago Silva got in the way of a Gabriel Martinelli shot. Another vital sliding interception drew roars of admiration from fans and team-mates alike.
Raya atoned for losing possession to Palmer by staying upright to stop him turning the ball into the unguarded goal, and then Jackson found the Spaniard in his way with his first touch after replacing Mudryk.
Arsenal were handed a way back into the game with 13 minutes remaining when an errant Sanchez pass was swept into the empty net by Rice.
Seven minutes later, the Gunners levelled when Saka’s deep cross was converted by Trossard, introduced after Arsenal’s first.
That was to prove the end of the drama, with Jackson forcing Raya into a low save with this entertaining derby's final chance.
What it means
The point moves us into the top half of the Premier League table for now, but the wait for a home win over Arsenal goes on. The draw does at least put an end to our losing streak at home in the league.
What’s next
The Blues are back at the Bridge on Saturday for another London derby. This time Brentford are the visitors to SW6.
Chelsea (4-2-3-1): Sanchez; Gusto, Thiago Silva, Colwill, Cucurella; Caicedo, Enzo; Sterling (Madueke 84), Gallagher (c), Mudryk (Jackson 66); Palmer (James 84),
Unused subs Petrovic, Maatsen, Badiashile, Disasi, Ugochukwu, Washington
Scorers Palmer (pen) 15, Mudryk 48
Booked Palmer 8, Thiago Silva 44, Cucurella 71
Arsenal (4-2-3-1): Raya; White, Saliba, Gabriel, Zinchenko (Tomiyasu h/t); Jorginho (Smith Rowe 68), Rice; Saka, Odegaard (c) (Havertz 78), Martinelli (Trossard 78); Jesus (Nketiah 68)
Unused subs Hein, Kiwior, Partey, Nelson
Scorers Rice 77, Trossard 84
Booked Zinchenko 11, Nketiah 89, White 90+1
Referee Chris Kavanagh
Crowd 39,723