Report: Derrius Guice initially diagnosed with sprained MCL

Washington Redskins rookie running back Derrius Guice was initially diagnosed with a sprained MCL after suffering a knee injury in Thursday night's preseason game, according to a source who spoke to NFL Network's Ian Rapoport.

Guice will undergo an MRI on Friday to confirm the extent of the injury.

Guice exited with 19 yards on six carries. He suffered the injury on a burst through the New England Patriots' defense. He gained 34 yards on the play but injured his knee during the tackle. The run was called back due to a holding penalty.

Though Robert Kelley took the first two carries of the game for the Redskins, Guice took over from there until he was sidelined. He's battling Kelley and Chris Thompson for the starting job.