The Cardinals placed safety Tyrann Mathieu and nose tackle Alameda Ta'amu on the physically unable to perform (PUP) list on Wednesday, two days before the team opens training camp at University of Phoenix Stadium.
Both players are recovering from torn ACLs (Mathieu also suffered a torn LCL), so the moves did not come as surprises.
The Cardinals are allowed keep both players on the PUP list when the regular season begins without them counting against the 53-man roster. However, a player who remains on PUP to start the regular season must wait at least six weeks before playing. Mathieu and Ta'amu are both expected to be ready before then and come off the list at any time.
Once a player practices, he must be removed from PUP list and can't return to it.
The team has not set any timetable on either player's return, although coach Bruce Arians during offseason workouts said he doesn't expect Mathieu to play until Week 5 after the team's Sept. 28 bye.
"That's strictly up to the doctors, trainers and them," Arians said. "I'm not going to hurry them. If they do something better than that, God bless 'em."
The Cardinals on Wednesday also released undrafted rookie wide receiver Kelsey Pope.