The New England Patriots have four defensive players listed as questionable for Sunday’s home game against the Titans.

Defensive end Ty Warren is among five Patriots players to open training camp on the physically unable to perform list. Also included on the list is LB Shawn Crable, offensive linemen Mark LeVoir and Rich Ohrnberger, and DL Darryl Richard.

The team also placed CB Shawn Springs and WR Brandon Tate on the active non-football injury list.

Patriots DE Ty Warren told the Boston Globe that he expects to be ready for training camp in July after undergoing double groin surgery in January.