Backup running back Lance Dunbar is in a walking boot, nursing a sprained left foot. He missed practice Monday as the team returned home to Valley Ranch, and the injury threatens his availability for start of the regular season.
The Cowboys had been counting on Dunbar to backup DeMarco Murray after Dunbar had a good camp. Dunbar had one carry for 2 yards and two catches for 61 yards, losing a fumble on a 43-yard gain, before leaving Saturday's loss to the Cardinals.
Dunbar's injury leaves rookie Joseph Randle and Phillip Tanner behind Murray. Tanner played on special teams against the Cardinals but did not take any offensive snaps.
The Cowboys, who began practice at 8:30 a.m. to try to beat the Texas heat, also were without WR Cole Beasley (foot), OG Ryan Cook (back), OG Nate Livings (knee), OG Ron Leary (knee), DE Toby Jackson (groin), LB Alex Albright (back), defensive tackle Jay Ratliff (hamstring), CB Morris Claiborne (knee), S Eric Frampton (hamstring), S Matt Johnson (ankle/foot), DT Sean Lissemore (groin), LB Ernie Sims (groin), DT Travis Chappelear and S J.J. Wilcox (personal).
Guards Kevin Kowalski (knee) and Ray Dominguez (shoulder) returned to practice.
-- Charean Williams