RICHMOND – Backup running back Tristan Davis has decided to give up on football, Redskins Coach Mike Shanahan said.

A member of Washington’s practice squad in 2011, Davis missed all of 2012 after injuring his knee in the final preseason game and this season found himself in a crowded competition for a spot behind Alfred Morris.

Third-year players Roy Helu and Evan Royster, fourth-year pro Keiland Williams and rookies Chris Thompson and Jawan Jamison all are battling for spots on Washington’s depth chart. Davis, who has had stints on the Detroit, Miami, Minnesota, New Orleans and Pittsburgh’s practice squads from 2009-2011, apparently grew tired of the game.

“Tristan Davis came to my office early this morning and said that his heart wasn’t into playing football anymore, and so he retired. Unless he changes his mind, that’s where he’s at,” Shanahan said.

Davis is the second running back in the last three seasons, and the third player in consecutive years, to quit the team during training camp.

In 2011, running back James Davis quit the team, unhappy with his spot on the depth chart. Then last summer, defensive end Kentwan Balmer left the team without informing team officials of his decision.

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