Bolton boss Owen Coyle expects defender Zat Knight to be out of action for four to six weeks with the knee ligament injury he suffered in Sunday's win over Everton.
The 30-year-old damaged his right knee in a last-ditch tackle on Victor Anichebe during the first half of the 2-0 victory and was carried off on a stretcher.
Coyle admitted the news could easily have been worse but Knight has formed an impressive partnership with Gary Cahill and his loss is a setback for the Trotters.
Coyle said: "Zat suffered ligament damage. It's not as severe as we first thought but certainly bad enough to keep him out for a period of time. There's severe swelling in the area so I think we'll know better in seven to 10 days when that goes down.
"But I think it's fair to say he'll be four to six weeks, which is a terrible loss, first and foremost for Zat, because he's played every game for me since I came to the football club over a year ago.
"He's been outstanding as a player and as a man and the sooner we get him back the better. It is a blow, there's no doubt about it, and we wish him a speedy recovery."