Cardinals quarterback Carson Palmer (left) and tight end Jermaine Gresham discuss formations after Wednesday's QB school workout at University of Phoenix Stadium.

Jermaine Gresham had back surgery this offseason, one of the reasons the veteran tight end didn't sign with the Cardinals until late July.

So it's not a big surprise the Cards placed him on the Physically Unable to Perform list Wednesday. What was a small surprise was the release of veteran cornerback Alfonzo Dennard, who had been claimed off waivers May 6.

Dennard's release leaves eight cornerbacks for the Cardinals and an open roster spot.

Gresham attended Wednesday's "QB school" workout and spent a few minutes afterward going over formations with quarterback Carson Palmer. He will be unable to take part in team work until he is removed from PUP. That can happen at any point during training camp, which is what happened last year when safety Tyrann Mathieu and nose tackle Alameda Ta'amu started training camp on PUP before eventually coming off a few weeks into practice.

The Cardinals also put tight end Troy Niklas (hamstring) and linebacker Zack Wagenmann (foot) on the active non-football-injury list.

Gresham had his surgery to repair a herniated disc in mid-March.

The Cards have another QB school workout Thursday, with the entire team reporting for training camp – and going through the conditioning test – on Friday. The team's first official practice is Saturday.

The Cards also waived/non-football-injury wide receiver Damond Powell, who was shot in the face last week. Powell reverted to the Cardinals' reserve-non-football-injury list Wednesday.