Wigan manager Roberto Martinez fears Ivan Ramis has suffered a cruciate ligament injury that could end his season.
The Spanish centre-back had to be taken off on a stretcher toward the end of the 1-1 draw with Fulham at Craven Cottage. Ramis appeared to twist his knee in a tackle with Dimitar Berbatov and Martinez expects bad news for the summer signing.
"That is the real negative of the afternoon," the Wigan boss said. "I thought Ivan was outstanding throughout the game. I think you are starting to see a centre-half that has adapted to the British game and is someone very, very important."
Martinez added: "I wouldn't want to say anything before seeing the scans, but I fear the worst. He has damaged the ligaments in the right knee and the signs are not great. I expect the worst, cruciate ligament."
It was an unfortunate end to a hard-fought encounter, which Wigan deservedly took a point from. Giorgos Karagounis' fantastic first-half strike put Fulham ahead but Franco di Santo levelled in equally impressive fashion, cutting in from the left to unleash a fierce drive past Mark Schwarzer.
"I am very, very pleased with the performance," Martinez said. "I think we started the game really brightly and carried a very good threat in the the attacking third. The goal came a little bit against the run of play and from that moment on it would be all too easy to accept the momentum was Fulham's.
"But I thought we restricted Fulham really well and they only had two shots on target - the goal and right at the end, with Maynor Figueroa's special clearance. In between those two actions I thought we were the better side. We defended really, really well."
Martinez might have left Craven Cottage satisfied but Fulham counterpart Martin Jol certainly was not. The result means the Londoners have now failed to win in four successive home matches in all competitions, with the last victory coming against Newcastle on December 10.
"It is always the same story," Jol said. "You go one up and you need another goal but cannot score another goal and then you are vulnerable. It is easier said than done but when you are 1-0 up you still have to dominate the game. We had a little problem to contain them and they had players in the pockets but we are a big team at the back.
"But we needed a second goal and we did not score a second goal. It was the same against Southampton when we needed second goal and didn't score and they scored an equaliser. We have a problem in our balance but we have quality and that will pull us through but we have to score two goals."