Cowboys release RB Ryan Williams

IRVING, Texas (AP) -- Ryan Williams, one of the possible replacements for NFL rushing champion DeMarco Murray, has been released by the Cowboys.

The oft-injured Williams was among three players cut Tuesday before the team left for training camp in Oxnard, California. The first workout is Thursday.

The 25-year-old Williams was a second-round pick by Arizona in 2011 but has appeared in just five games because of knee and shoulder injuries. He missed most of this offseason with knee problems.

The Cowboys signed running back Gus Johnson, an undrafted rookie out of Stephen F. Austin. He will join a group led by Joseph Randle, Darren McFadden and Lance Dunbar.

Dallas also signed center Ronald Patrick while releasing linebacker Cameron Lawrence and tackle Ryan Miller.