Broncos running back Montee Ball will undergo an emergency appendectomy, according to a report from The Denver Post.

Ball has been the starting running back since Knowshon Moreno decided to leave for Miami in free agency. Now, Ball will have to take some time to recover. He is expected to be back by the regular season opener on Sept. 7.

Ball isn't expected to play in any of the preseason games, the report states, as he recovers from the procedure.

He finished the 2013 season with 559 yards and four touchdowns.

Ball should still be able to step back in as Denver's starting running back once he's able to return. He was able to get in a lot of work prior to this setback and is the most talented of the group that also features Ronnie Hillman and C.J. Anderson.

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