Philadelphia Eagles center Jason Kelce retired on March 4. Two days later, he explained why during his podcast and expressed disappointment with how last season ended.

Jason Kelce never revealed the “why” when he announced his retirement from the Philadelphia Eagles and the NFL in an epic 42-minute speech on Monday.

Two days later, on his ‘New Heights’ podcast with his brother Travis, Kelce explained the why of calling it a career now, at 36, and after spending all 13 of his NFL seasons in Philly.

Think body parts.

“My elbows and my knees, it’s just gotten to the point where deterioration and the recovery from that deterioration hasn’t really manifested on game day, yet, but I know it’s gonna start doing that,” he said.

Kelce said retirement is something he thought about for the past several years, as had widely been reported, always saying that he would know when it’s time. And he is confident that the time is now.

“I think it got to the point where I know that’s what I wanted to do,” he said. “The reality was, it was more firm than it’s ever been this year that I just don’t think physically I can compete at that level anymore.

“…I’m hard on myself and if I go out there and I’m not the player that I want to be, it will crush me. I feel very confident in the decision I’ve made. I know it’s time. I’ve had a really good run,” Kelce said.

The longtime center, who appears destined for enshrinement in the 2029 class of the Pro Football Hall of Fame, also revealed on his podcast his displeasure over retiring now, after the way last season ended with a 10-1 start unraveling to a 1-6 finish.

“The one thing I’m disappointed about retiring right now is I’m retiring when the Eagles had potentially the biggest collapse in the history of the organization,” he said. “Not potentially, probably the most. The reason I say that I’m upset about that is — I really, truly think the Eagles are going to ball out next year.”

The talent cupboard is far from bare for the Eagles, though losing Kelce will require new leaders to step on the offensive side of the ball, and perhaps quarterback Jalen Hurts will take his leadership style up a few notches without Kelce being present.

“They’ve hired two really good coaches that are going to be able to offer a new perspective and look at things with a fresh lens,” he said. “I think Jalen Hurts is a tremendous quarterback, I know it wasn’t a good end of the year for him or for anybody on offense, but there’s still so many pieces.”

“There’s plenty of cap space,” Kelce said. “I know (general manager) Howie (Roseman) is going to make some moves to improve the things that need to get fixed.”

Kelce will watch what happens next from afar, though it’s unlikely he will be too far away.