Manchester City defender Aleksandar Kolarov, midfielder Frank Lampard and playmaker David Silva will miss Wednesday's Champions League match against CSKA Moscow, coach Manuel Pellegrini said on Tuesday.
Kolarov missed Sunday's derby win over Manchester United with a calf injury and will be out for a month, while Lampard, who said on Monday he hoped to recover in time from a thigh injury, should be fit by next week.
City will also be without Silva who injured his knee in last week's home Capital One (League) Cup loss to Newcastle United.
The Premier League champions have only two points from three matches in Group E and must beat CSKA to keep alive any realistic chances of advancing to the last 16.
"Kolarov has a muscle injury in his calf and will be out for at least one month, and I think Frank will be fit next week," Pellegrini told reporters.
Lampard, who won the Champions League with Chelsea in 2012, has been sidelined for two weeks but had told the club's website (www.mcfc.co.uk) the injury was not as bad as he thought.
"I'm not far off selection," he said. "Fingers crossed, if all goes well over the next couple of days, I'll be back in contention. I had a small injury in my thigh -- an old injury I'd disturbed slightly."
Lampard said he was amazed at how much he was enjoying life at Manchester City, where is on loan from Major League Soccer club New York City.
He has scored four goals in seven appearances for the club, including a late equaliser against Chelsea in September.
"It's a great opportunity -- not many at 36 get the chance to come and play for a club like City," he said.
"I love the training, living up here, the people at the club, the staff and the fans.
"When I left Chelsea, I thought I was going to be moving out of the Premier League and that was a different angle. That's all to come still but this is an absolutely brilliant time for me.
"I want to look back on it and say I enjoyed it -- but more than that, I want to look back and say I made a bit of a difference in a positive way."
Lampard is contracted to City until the end of December but there has been speculation he could stay at the Etihad for the remainder of the season.
"I said two months ago when the news started that we would wait till December before deciding what to do," Pellegrini said.
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