Williams described the injury Friday as irritation of the "fatty pad under patella tendon," which was repaired in August 2011.
By Saturday, Williams was sporting crutches after undergoing further treatment on the knee, according to The Arizona Republic. Coach Bruce Arians hopes to have him back on the field by next week, though Williams has said there's no timetable for his return.
Williams isn't the only Arizona tailback dealing with knee issues. Rashard Mendenhall was held out of Saturday's practice with knee tendinitis. After downplaying Mendenhall's injury, Arians said he expects his starter back in a couple of days.
With Mendenhall and Williams sidelined, we got a glimpse of a proto depth chart on Saturday. Fifth-round draft pick Stepfan Taylor worked as the starter, followed by Alfonso Smith and sixth-round draft pick Andre Ellington. The latter two likely are battling for one roster spot unless Williams suffers another setback.The Around The League Podcast is now available on iTunes! Click here to listen and subscribe.