Zastudil was ruled out of Sunday's game against the San Francisco 49ers a few hours later with a left groin injury after not practicing Thursday or Friday. He has yet to punt this season because of the nagging injury, which is expected to fully heal during the Cardinals' bye week. He was active in Week 1 to act as a holder for rookie kicker Chandler Catanzaro and inactive in Week 2. Butler has eight punts for an average of 44.2 yards.
Linebacker Alex Okafor is also out for Sunday's game with a thigh injury.
Running back Andre Ellington (foot) was upgraded to probable for Sunday after being limited in practice Thursday and Friday.
Getting Rucker back would add depth to a pass rush that was depleted with the loss of outside linebacker John Abraham.
"We feel real good that he's going to test it before the game," Cardinals coach Bruce Arians said. "He was limited today. He's battle tested, especially in this type of game."