CSKA Moscow and Japanese midfielder Keisuke Honda will be sidelined two to three months with a knee injury.
Honda, 25, was injured in Sunday's Russian league match against Spartak Moscow and was forced to leave at halftime. It was later revealed the Japan national team player needed immediate surgery.
CSKA previously lost No. 1 goalkeeper Igor Akinfeev for six months and will be short on options now that Honda is injured when the Champions League starts in two weeks.
The Russian club is in Group B with Inter Milan, Lille and Trabzonspor.