The Lions placed Zylstra (ankle) on injured reserve Tuesday.
Zylstra suffered an ankle injury during the Lions' Week 2 win over the Bears. He is required to miss at least the next four games, which makes Week 7 against the Buccaneers on Sunday, Oct. 20 the earliest he can return. Sam LaPorta and Brock Wright are the Lions' two lone tight ends on the 53-man roster, but Detroit shored up its depth at the position by signing Ross Dwelley to the practice squad.