Williams (hamstring) got the first snap Monday in team drills, Adam Teicher of ESPN.com reports.
Williams returned to practice Wednesday as a limited participant but was held out of Saturday's preseason opener against Cincinnati. Coach Andy Reid expressed some concern about the running back's extended absence from training camp, noting that Carlos Hyde was taking advantage of the opportunity. A strong showing from Darwin Thompson on Saturday further contributed to the concern surrounding Williams, but a return to full participation Monday gives the veteran plenty of time to solidify his role before Week 1. Reid and offensive coordinator Eric Bieniemy both made it clear during the offseason that they view Williams as their starting running back.