Bolton defender Tyrone Mears has suffered a broken leg after a challenge in training.
The 28-year-old, who only moved to the Reebok Stadium last week from Burnley, is now likely to be out for a lengthy period.
Trotters manager Owen Coyle told the club's website: "Ty went in for a challenge and unfortunately suffered the injury.
"It was desperately unlucky for him and we will make sure that he is fully supported in his rehabilitation.
"He will go for a check and an assessment in a month and that will indicate more accurately the timescale for his recovery."
Mears is the second Bolton player to suffer a broken leg in less than a week after Lee Chung-Yong was ruled out for nine months following an injury he picked up in a friendly against Newport County.