Detroit Lions great Frank Ragnow details his abrupt retirement, failed comeback attempt

Ragnow, 30, retired abruptly during the summer, announcing his retirement on social media. In November, he tried to make a return to the field and sign with the Lions, only to fail his physical because of a Grade 3 hamstring strain.

"But it's just, like, I was uncomfortable, and it's one of those things where you have a couple kids, and I don't want a sob story," Ragnow said. "I'm going to be completely fine and everything, but it's one of those there where, like, 'Is the juice worth the squeeze' thing, and, to me, ultimately it came down to that decision, and, obviously, I struggled with that decision too."

Ragnow said he continued to stay in shape, which is why he attempted to return to the sport in November. He said he knew his hamstring was sore but had no idea how bad the injury was.

"I got hurt a day or two before I got there, and it's unfortunate. I should've listened to my body probably, but it is what it is," Ragnow said. "It's a learning experience, and at least I can say I laid my head on the pillow at night and said I tried. I tried for the team. I tried for the fans. And it just wasn't meant to be."

The center made the Pro Bowl in consecutive seasons after signing the contract, and he remained one of the best centers in the sport despite battling injuries throughout his career. In his final season, Ragnow played through a partially torn pectoral muscle and still played in 16 games.