ANN ARBOR, Mich. (AP) -- Michigan coach Jim Harbaugh says quarterback Wilton Speight has some cracks in his vertebrae.
Harbaugh says he doesn't know whether Speight will be out for the year, but he will miss multiple weeks.
Harbaugh says John O'Korn will make a second straight start when the 17th-ranked Wolverines play Saturday at Indiana. O'Korn threw three interceptions in a 14-10 loss to Michigan State in his first start of the season.
Speight was hurt in the first quarter of last month's victory at Purdue.