Mohamed Diame is out of Wigan's Christmas and New Year campaign and the 22-year-old French midfielder is to undergo a second scan on a knee ligament injury sustained during Wednesday's 2-1 defeat at Liverpool.
Although the results of Thursday's first scan proved inconclusive, boss Roberto Martinez has already ruled Diame out of the festive programme, meaning he will be sidelined for at least four matches.
Diame has started every game for Wigan, and been an influential figure in their midfield, since his move from Rayo Vallecano in late August.
But he now misses the local derbies at home to Bolton on Monday and Blackburn on Boxing Day, followed by a trip to Manchester United on December 30 and then the FA Cup third-round tie with Hull at the DW Stadium on January 2.
"He was involved in a tough challenge on Wednesday. It was a football accident and the knee opened up,'' said Martinez on the incident that saw Diame hobble off just before the hour at Anfield. "At the moment we think he has a little problem with the lateral ligament in his left knee.
"We need to see the extent of the problem, but it's a question of weeks rather than months. We hope it will be between two and three weeks, but it's too early to call at the moment, although he's gone for the Christmas and New Year period.
"He had one scan yesterday, but that wasn't too clear because of the inflammation around the area, with the cartilage and meniscus affected. So he'll probably have another scan tomorrow or Monday, with the next 48 hours important. But he is a very fit boy and sometimes you settle quicker than the injury itself.
"With the light numbers we have in the squad, though, any injury is a big blow for us. Momo has been in good form. He started well against Liverpool, so naturally it's disappointing to lose him.''
Jason Scotland, who replaced Diame at Anfield, is almost certain to return to the starting line-up as Martinez reverts to playing two in attack against Bolton.
Despite the injury, Martinez at least feels the break will serve his player good in the long run.
"The Premier League is really intense, and Momo's had a lot of football already for such a young man,'' added the Spaniard. "So we'll refresh him and make sure he is perfect and ready for the second half of the campaign. It's another opportunity for someone else in the squad, and that's the way we need to treat it.''