Groce said Tuesday that Illinois (3-4) is preparing as if the 6-foot-11-inch starting center will not be back, because the meniscus tear Thorne suffered Saturday against Iowa State ''absolutely'' could be season-ending.
Thorne had surgery Monday and Groce said it is too soon to know how his recovery will go. He added that Thorne's Type 1 diabetes could also be a factor.
Groce does not yet know whether the fifth-year senior could redshirt.
Thorne is the team's leading rebounder with 8.4 a game and is averaging 13.4 points.
Illinois hosts Notre Dame (4-2) on Wednesday.