Doug Martin has a torn labrum in his left shoulder but the Bucs won't place him on Injured Reserve right away and are hopeful he can return later this season.
Martin, who led all rookies with 1,454 rushing yards and 11 touchdowns last season to earn his first selection to the Pro Bowl, was injured attempting to catch a pass early in the third quarter of the Bucs' 31-20 loss to the Atlanta Falcons Sunday.
After the game, Martin was hopeful the injury wasn't serious and x-rays should no separation. But an MRI exam Monday morning revealed the torn labrum.
With Martin out, the Bucs will turn to rookie running back Mike James, a sixth-round pick from Miami, beginning with Thursday's game against the Carolina Panthers. James has 57 yards on 17 carries this season. The team also will use running back Brian Leonard, especially on third down and short yardage situations.
Bucs safety Dashon Goldson also had an MRI on his knee after leaving Sunday's game against Atlanta. Results of that examination have not been disclosed.