Manchester City captain Vincent Kompany may not be fit before the end of the season because of a muscle injury, manager Manuel Pellegrini said on Friday.
The 29-year-old central defender limped off at halftime during last weekend's 4-2 derby defeat by Manchester United and could miss City's remaining six games of the campaign.
"We don't know how many weeks he will be out for," Pellegrini told a news conference. "He has a muscle injury. We don't know if he will be fit from now to the end of the season."
Kompany is joined on the sidelines for Sunday's visit of West Ham United by forwards Stevan Jovetic and Wilfried Bony, midfielder James Milner and defender Gael Clichy.
Champions City have dropped to fourth after losing four of their last six league matches and media speculation suggests Pellegrini will be out of a job at the end of the season.
"That (speculation) is the same, every time you manage at a big club," Pellegrini said. "It doesn't just happen here.
"It is the worst period of results since I arrived and 2015 has been a very bad year.
"If you don't get the results the club deserves, everybody talks about changing the manager. That's here, in Spain, in every part of the world.
"So you must be used to that. You can't be happy when you're out of the fight for the title. But it is very easy to say that the diagnostic is to sack the manager."
Former Real Madrid coach Pellegrini said he would take stock of City's situation at the end of the season but believes they can still finish the campaign on a high.
"The players always have my support," he said. "With trust, we can recover. It's important to be in the Champions League.
"Every time you finish a season you must analyse whether you're winning or losing.
"If we lost the last six games we won't have the same conclusions as if we win the next six. Maybe you can finish second or eighth -- it's impossible to analyse before the end."
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