Broncos release tailback J.J. Arrington

ENGLEWOOD, Colo. -- The Denver Broncos have released tailback J.J. Arrington after he failed a physical due to a balky right knee.

The team confirmed the move Thursday.

Arrington was one of three veteran tailbacks the Broncos brought in during the offseason, along with Correll Buckhalter and LaMont Jordan, after a year when the team placed an astonishing seven running backs on injured reserve.

The Broncos also selected Knowshon Moreno with the 12th pick in the draft to bolster the backfield.

Arrington signed a four-year deal worth about $10 million in early March. He figured to be a third-down specialist for the Broncos in 2009, a role similar to the one he played last season for the NFC champion Arizona Cardinals.