Blues won 3-2 after being 0-2 down at half-time
West Ham were leading 2-0 before a late surge from the hosts denied victory
Enzo Fernandez scored in stoppage time
Chelsea recovered from 2-0 down at half-time to win a Premier League match for the very first time, with Enzo Fernandez scoring in stoppage time to secure a 3-2 win over West Ham.
Nuno Espirito Santo's resurgent Hammers were on course for a third straight Premier League win at the interval, having ruthlessly punished a lacklustre Chelsea display.
Having made six changes to the team that beat Crystal Palace last week, Liam Rosenior saw his team fall behind when Jarrod Bowen's seventh-minute cross curled all the way in.
Crysencio Summerville's fizzing finish doubled West Ham's tally in the 36th minute, leading to Rosenior making three changes at half-time, introducing Joao Pedro, Wesley Fofana and Marc Cucurella, and all three had key roles to play in Chelsea's fightback.
Fofana stepped out of the backline to supply a wonderful cross as Joao Pedro made it 2-1 in the 57th minute, then Cucurella pounced with a diving header to make it 2-2, after Liam Delap nodded against the crossbar under pressure from Maximilian Kilman.
Jean-Clair Todibo somehow prodded against the post with the goal gaping, and Chelsea made that reprieve count as Joao Pedro cut the ball back for Fernandez to sweep home, on the eve of the three-year anniversary of his arrival at Stamford Bridge.
Tempers then boiled over in the closing stages, and Todibo was sent off for grabbing Joao Pedro around the throat, compounding West Ham's woes.
They remain 18th, five points adrift of Nottingham Forest, while Chelsea climb into the top four ahead of Manchester United's meeting with Fulham on Sunday.
Data Debrief: Chelsea show powers of recovery
Chelsea had never before tasted victory in a Premier League match after trailing by at least two goals at half-time, while it is only West Ham's second defeat in the competition after leading 2-0 at the interval (also 2-3 versus Wigan Athletic in May 2011).
Rosenior may have been regretting his decision to shuffle his pack at half-time, but his substitutions made the difference.
In Joao Pedro and Cucurella, this was the first instance of two substitutes scoring for Chelsea in a single Premier League match since September 2022 – also against West Ham (Ben Chilwell and Kai Havertz).
And Joao Pedro's goal, assisted by Fofana, was the first time two substitutes combined to score a Premier League goal for Chelsea since Jadon Sancho assisted Christopher Nkunku's winner against Bournemouth in September 2024.
At the end of 101 chaotic minutes, Rosenior became the fourth Englishman to win his first three matches as a Premier League manager, after Bobby Gould in August 1992, Sam Allardyce in August 2001 and Craig Shakespeare (first five) in April 2017.
