FRISCO, Texas -- Tight end James Hanna is walking away from football in part because of a knee condition that has troubled him for most of the past two seasons.

The Dallas Cowboys will place Hanna on the reserve/retired list.

Hanna missed the 2016 season after undergoing surgery to deal with an arthritic condition. He returned last season and played in every game, starting eight of them.

The Cowboys gain $2.75 million in salary-cap space with the move. Hanna had not been involved in the early part of the Cowboys' offseason program.

Hanna said his body "felt more vulnerable than it had," in dealing with the knee issues and he did not want to risk further injury that would affect his way of life as he gets older. But he has no regrets.

"The dream was to play for the Cowboys," Hanna said. "I don't know how many people actually do what they say they're going to do as like a 13-year-old. But I consider myself to be extremely lucky in that sense. Also the college I went to [Oklahoma], I feel like I met my goals. It would've been nice to have more stats and obviously I could've done more things, but I'm proud of what I accomplished.”

Hanna, 28, came to the Cowboys as a sixth-round pick in 2012 with the reputation as a pass-catcher but developed into a dependable blocker at No. 2 tight end. He started 37 of his 78 career games and finished with 37 receptions for 374 yards and a touchdown.

The Cowboys enter the upcoming draft with tight end among their top needs with Jason Witten entering his 16th season. Hanna and Geoff Swaim were set to be unrestricted free agents in 2019. Blake Jarwin and Rico Gathers have yet to catch a pass in a regular-season game.

The Cowboys did not have a tight end among their top-30 national visitors but have had a few private workouts with some during the draft process.