The Cowboys have signed an eighth player to the practice squad on Thursday, adding defensive tackle Robert Callaway.
Last year, Callaway spent the entire 2010 season on the Lions' practice squad. He signed with Detroit as an undrafted free agent from Saginaw Valley.
The Cowboys were hopeful former draft pick Sam Young would be able to fill out the practice squad. But Young was claimed off waivers by the Bills on Monday, keeping just three tackles on the practice field this week.
With Callaway now signed, the Cowboys practice squad consists of WR Teddy Williams, CB Mario Butler, LB Orie Lemon, LB Isaiah Greenhouse, WR Andre Holmes, S Akwasi Owusu-Ansah, FB Shaun Chapas and Calloway.