Diego Costa's late goal helped Chelsea defeat West Ham 2-1 and made Antonio Conte a winner in his debut as manager at Stamford Bridge on Monday.
Eden Hazard's penalty early in the second half had put Chelsea ahead, and Conte's side looked to be in full control until James Collins' equaliser in the 77th minute.
But Costa, who was perhaps fortunate to still be on the pitch after a wild tackle, struck in the 89th minute to give Chelsea all three points.
Chelsea's first chance to take the lead came in the 12th minute as Branislav Ivanovic got forward into the box and cut inside, only for Adrian to make a diving save at the near post.
Oscar then had a penalty shout waved away after going down in the box, and a minute later Diego Costa was booked for confronting referee Anthony Taylor.
Hazard provided Chelsea's best opportunity of the first half when he ran into the box and sent a diagonal shot inches past the far post.
West Ham's Andre Ayew pulled up with an apparent injury on the play and was replaced by fellow new signing Gokhan Tore, before the first half ended with Adrian tipping Willian's free kick over the bar.
But Chelsea were awarded a penalty within a minute of the start of the second half as Michail Antonio bundled into the back of Cesar Azpilicueta.
Eden Hazard made no mistake from the spot, sending a powerful shot down the middle to give Chelsea the lead.
Costa then escaped a second booking when he caught Adrian's leg while trying to dispossess the goalkeeper in his box in the 68th minute.
West Ham never looked like scoring until Collins struck in the 77th minute. The play began when Azpilicueta caught Andy Carroll with a high boot and was booked for dissent, and Dimitri Payet's free kick came off the Chelsea wall for a corner.
The Hammers were shouting for a penalty when Azpilicueta blocked Enner Valencia's volley from close range, but the ball fell for Collins to smash home and level the score.
Like Costa and Azpilicueta before him, Chelsea's N'Golo Kante, who had been booked for a challenge three minutes into the match, also escaped a second yellow card for a challenge on Payet with six minutes to play.
Michy Batshuayi made his Chelsea debut when he came on in the 85th minute, and he proved instrumental in the winner, heading the ball on for Costa, who struck with a low shot from the top of the 18-yard box, much to the delight of his new manager.