Cardinals coach Bruce Arians said Sunday that he’s not sure running back Ryan Williams (right knee) will play this week. Last week Williams guaranteed he would play against the Cowboys on Saturday but it appears his knee is still not healed creating further doubt about his future with the club. Williams has played just five NFL games through his first two seasons due to knee and shoulder injuries. Arians hopes running back Andre Ellington (concussion) will be able to go Saturday. The Cardinals went with two backs in Green Bay electing to hold Rashard Mendenhall (knee tendinitis) out as a precaution. Alfonso Smith and Stepfan Taylor were the only backs to carry the ball.