Arsenal manager Arsene Wenger admitted "something has gone" within the team after they came off second best against Stoke in a 3-1 defeat at the Britannia Stadium.
Goals from Kenwyne Jones and Jermaine Pennant put the hosts in control in the first half and, even when Robin van Persie pulled one back late on, Jon Walters replied immediately to snuff out any thoughts of a comeback.
It ended any outside chance the Gunners had of forging a late run to the top of the table.
"Something has gone - you can see that," said Wenger. "It was a disappointing performance. The competitive level for Stoke was higher than ours and overall I think we lost the game because Stoke defended much better than we did, with much more purpose. Basically, there is not a lot to say."
Last weekend Arsenal beat leaders Manchester United to reignite hopes of catching Sir Alex Ferguson's side, but those chances were quashed in clinical style by a committed Stoke team who could have been forgiven for having their minds elsewhere with an FA Cup final appearance just six days away.
"That is the Premier League. If you don't turn up it is the same competitive spirit in every game and you can lose everywhere, especially at Stoke," Wenger said.