West Bromwich Albion ended Arsenal's streak of eight straight away wins in the Premier League by holding the league leaders to a 1-1 draw at home Sunday.
Arsenal couldn't match the fluidity they displayed in their 2-0 dismantling of Napoli in the Champions League midweek, and West Brom took a 1-0 lead into halftime after Claudio Yacob's header in the 42nd.
Arsenal improved in the second half after Tomas Rosicky came on as a substitute, and he helped set up Jack Wilshere for the equaliser in the 63rd as the England midfielder fired in a shot from outside the area.
The point was enough to keep Arsenal atop the Premier League table, although they are now level with Liverpool on points and goal difference.
Ravel Morrison's skillful solo goal for West Ham completed a 3-0 victory over Tottenham in style as a 14-year wait for a win at its London rival in the Premier League ended.
Morrison picked up possession inside his own half and swept past both Michael Dawson and Jan Vertonghen before dinking the ball over goalkeeper Hugo Lloris in the 79th minute.
An ultra-defensive formation had seen West Ham struggle to threaten Tottenham's goal until Winston Reid opened the scoring in the 66th.
Then Ricardo Vaz Te fortuitously added another six minutes later, with the ball coming off his knee after Lloris blocked an initial shot.
West Ham's first win at White Hart Lane since 1999 lifted the team to 13th. Tottenham are out of the top four in sixth.
Substitutes Eden Hazard and Willian scored inside two second-half minutes to steer Chelsea to a 3-1 victory at Norwich in the Premier League.
Oscar was the first of the three Chelsea midfielders to find the net at Carrow Road in the 4th minute.
After Anthony Pilkington headed Norwich level in the 68th, Chelsea manager Jose Mourinho brought on Hazard and Willian off the bench.
Chelsea's lead was restored in the 85th after Norwich conceded possession from its corner and the visitors launched a blistering counterattack. After Alex Tetty failed to clear the ball, Hazard took advantage and unleashed a shot that squirmed under goalkeeper John Ruddy.
Willian was on target in the 86th on his Premier League debut with a curling strike that landed in the top corner.
Adam Lallana and Jay Rodriguez scored to give Southampton their third successive Premier League victory with a 2-0 win over Swansea.
The match between two sides known for their attractive style lived up the billing, with play flowing from end to end in an entertaining encounter at St Mary's. Lallana gave the hosts the lead in 19th but Swansea dominated after that, only for substitute Rodriguez to take advantage of slack defending to seal the win in the 83rd for Mauricio Pochettino's side.
Lallana latched on to a neat ball from Steven Davis to put Saints ahead, but Swansea then forced Artur Boruc into fine saves to stop Michu and Wilfried Bony.
Nathan Dyer also hit the inside of the post shortly before halftime.