Matthew Stafford worked with the first team at practice Thursday, a sign of progress after he hurt his ankle last weekend. "He has improved," coach Jim Schwartz said. "I think that he's on a pretty good track right now." Stafford hurt his right ankle late in Sunday's 23-16 loss to Atlanta, hobbling off the field after a fourth down incompletion, but it was hard to tell how serious the injury was because the Lions never got the ball back after Stafford came off. Detroit plays at Denver this Sunday. Stafford has completed 60 percent of his passes this season, for 1,912 yards with 16 touchdowns and four interceptions.