Real Madrid's Cristiano Ronaldo is out of Wednesday's UEFA Champions League Group B match at home to Galatasaray due to a leg muscle strain, coach Carlo Ancelotti said on Tuesday.
The Portugal forward limped off at the start of the second half of Saturday's La Liga victory at Almeria and a scan on Monday confirmed he had damaged a hamstring.
The injury was not serious and Ronaldo might recover in time to feature in Saturday's La Liga match at home to Real Valladolid, Ancelotti told a news conference.
"Cristiano cannot play tomorrow," the Italian said. "He has picked up a very small problem. I think tomorrow he will start to work on his own on the pitch and we'll see if he can be available for Saturday.
"It's a muscle strain but the player is very confident he can play on Saturday.
"If there is a risk he could injure himself we will not use him. If he is fine then he'll play."
Ronaldo has netted 14 goals in his last seven games for club and country and his injury comes after a demanding start to the season during which he has played every match.
If Real avoid defeat against Galatasaray, whom they thrashed 6-1 in Istanbul in their opening game in September, they will qualify for the last 16 in first place.
The nine-times European champions top the group on 10 points from four of six matches. Galatasaray and FC Copenhagen each have four points and Juventus, who host Copenhagen on Wednesday, have three.
Ancelotti said Argentina winger Angel Di Maria or Spain under-21 forward Jese could replace Ronaldo in the starting lineup on Wednesday.
"It could be that we can play with Di Maria or Jese who played very well as a replacement for Cristiano against Almeria," he added. "We have two options and I will decide tomorrow."
Real's France centre back Raphael Varane was also unavailable for Wednesday as he needs to rest the knee that was operated on earlier this year, Ancelotti added.
"We had a meeting with the doctors and the player yesterday and decided that Varane needs a period of rest and recuperation for his knee.
"He won't be able to play for 10-12 days. We hope that with this period of recuperation the knee will not become inflamed. He doesn't need another operation, just rest."
Image: Cristiano Ronaldo
Photograph: Gonzalo Arroyo Moreno/Getty Images