Chelsea suffered more disappointment in the Premier League as Glenn Murray scored a late winner to secure a 1-0 win for Bournemouth at Stamford Bridge.
A lack of quality in front of goal prevented Jose Mourinho's side from continuing their recent resurgence as Murray came off the bench to condemn the champions to an eighth league defeat of the season.
The early signs were worrying for Bournemouth as Chelsea started brightly when Eden Hazard, who led the attack for the hosts once again, fired straight at Artur Boruc.
Despite an early scare, Bournemouth often looked the more threatening of the two sides in the first half as Chelsea struggled with their decision-making in the final third.
The returning Thibaut Courtois was kept busy in the opening 45 minutes as the Belgian made one save from Junior Stanislas with his legs, before getting a strong hand to Josh King's effort at the near post.
Courtois looked on helplessly just a few minutes later when Dan Gosling's deflected strike drifted over the crossbar after clever work from the midfielder and Harry Arter.
Chelsea continued to struggle to find space for their attacking quartet, and there was no doubt who looked the more likely to score as Courtois made another fine save to deny King, whose movement off the ball was a constant concern for the hosts.
After leaving Diego Costa on the bench in the goalless draw with Tottenham Hotspur last weekend, Mourinho turned to the striker to make an impact as his side started the second half strongly to push Bournemouth back.
Chelsea dominated for an extended spell as they searched for the opener, with Nemanja Matic heading over the crossbar before Boruc was forced into action to keep out a deflected effort from Branislav Ivanovic.
As Bournemouth dropped deeper in response to the pressure from the home side, Chelsea committed more men forward and the visitors were left breathing a huge sigh of relief when Adam Smith made a crucial block to prevent Costa from converting a cross on the slide at the back post.
The winner arrived with eight minutes of normal time remaining as Chelsea failed to deal with a corner, and with Courtois caught out of position, Murray headed home from close range despite appearing to be in an offside position beyond the Belgian goalkeeper.
Matt Ritchie could have wrapped up the game moments later when he sprinted clear on the break, but his effort crept inches past the post with Courtois looking beaten.
Chelsea struggled to produce a response to the setback as Bournemouth finished the stronger of the two teams, with Arter capitalising on a Gary Cahill mistake to shoot wide.
Gosling missed another chance to double the lead in stoppage time when he saw Courtois block an effort from close range after deciding against teeing up Stanislas, but it would quickly be forgotten as a memorable win for the Cherries was finally confirmed.
