By Zach Koons The injury marred an otherwise brilliant first half for the Wolverines ballcarrier. View the original article to see embedded media. Michigan star running back Blake Corum left Saturday’s game against Illinois after appearing to suffer a left knee injury late in the first half of the contest. The injury occurred as Corum, a Heisman hopeful, scurried his way upfield to the first down marker. As he neared the line to gain, an Illinois defender tackled him at the knees, sending the junior ballcarrier to the ground and jarring the ball loose. After Corum came to a rest on the field, …