Speaking about the injury, Latics boss Roberto Martinez said: "It was an unnecessary challenge. It was not malicious, but it was reckless. One of the most creative young players in the league is going to be out for up to 10 weeks. That is a football crime.
"It is a little bit better than we thought at first but it is obviously ligament damage in the right ankle. When it is swollen, it is sometimes difficult to assess but there is no fracture, we hope."
McCarthy was injured as he was tackled from behind (click here for a picture) by Bolton's Fabrice Muamba.
The Bolton midfielder has since apologised for the tackle but referee Howard Webb deemed no further punishment necessary as he gave only a free kick.
Perhaps a ten week spell on the sidelines for hte blue eyed boy of the FA refereeing register would be a fitting punishment.
Roberto Martinez revealed that he fearerd the worst when he saw the tackle and the need for a stretcher. He added: "When I saw him stretchered off, I feared for the worst. I think the level of performance from James this season has been so consistent for a young man.
"I know it's a long time off for him now, but we'll use that period to try and refresh him and regenerate his body to work in other areas. When he comes back, he'll probably be stronger."