Title-chasing Manchester City will be without striker Sergio Aguero for Saturday's Premier League clash at home to Sunderland after picking up a "stupid" foot injury, manager Roberto Mancini said on Friday.
"It is a stupid injury," Mancini said. "It was not his fault but he can't play with this injury; for one day, 10 days or two weeks, I don't know."
Mancini, who has Aguero's fellow Argentine Carlos Tevez available again, would not give details of the injury.
"I prefer not to say," he said. "But he couldn't play against Stoke and can't play tomorrow. I hope he can recover for Arsenal next weekend."
City, who are three points behind Manchester United, can return to the top with victory over Sunderland as United are not in action until Monday against Blackburn Rovers.
Tevez has made two appearances as a substitute since patching up his relationship with the club and Mancini said he could be ready for a larger role in City's eight remaining league games.
"He is improving but I don't think he can start," Mancini said. "But I think he can play more time, he is improving every week."
City could also welcome back defender Vincent Kompany after he missed the last four games with a hamstring injury.