Manchester United defender Nemanja Vidic has been ruled out for two months following knee surgery.
The 30-year-old missed a large chunk of last season after injuring his knee in December 2011, but returned to training in pre-season.
A statement on the club's official website read: "Nemanja Vidic has had a meniscus operation on his right knee and will be out for around eight weeks.
"Sir Alex, as a precautionary measure, rested Vidic at the weekend, after he complained of tightness in his knee, however, further medical investigation revealed the underlying problem.
"The central defender was operated on this week and will be sidelined for about eight weeks."
United are also without central defenders Phil Jones and Chris Smalling through injury.