Jason Kelce's ankles were taped at retirement conference. Here's why

Jason Kelce's longtime trainer is speaking out after Kelce was photographed with his ankles taped at his retirement press conference Monday.

Joseph O'Pella, an associate athletic trainer for the Philadelphia Eagles, explained in an Instagram post Tuesday that after he learned Kelce would retire, he told him he regretted not being the last person to tape the Eagles center's ankles -- after taping his ankles for the last decade -- as he had been away from work while undergoing cancer treatment.

"I taped this guy's ankles and thumbs everyday for 13 seasons, and when he played his last game in Tampa, again I couldn't be there due to cancer," O'Pella wrote in part. "And when he told me he would be retiring and I expressed my regret of not being the last person to ever tape him, and he offered to have me tape him for his retirement press conference. That's who he is. And I hope these stories can add to an already unbelievable legacy."

O'Pella said he and Kelce developed a strong relationship over the years and became close friends.

"You all know about the on-field accomplishments, and many of the off-the-field ones too, but what this man has meant to me and now my family over the past decade plus is nearly indescribable," O'Pella wrote. "From being his Wing Bowl 'cornerman', to hour long rehab sessions followed by nights out on the town, to sleeping on each other's couches to being at each other's weddings, to Sea Isle City Polar Bear Plunges to Super Bowl appearances and a ring, we were there doing it together."

After O'Pella was diagnosed with cancer, he said Kelce went above and beyond to support him and help him out as a friend.

"When I was diagnosed with cancer and had to undergo radiation and chemo, he offered his shore house if I needed to get away, and offered to pay for meal services to help my wife and I out, and he called me randomly when I had been home, too sick to come in bc of chemo, just to check on me and chat about random things," the trainer wrote. "That's who he is as a person."

When reached by "Good Morning America," the Eagles and O'Pella confirmed the content of O'Pella's Instagram post. O'Pella declined to comment further.

Kelce, widely considered one of the NFL's best centers, announced his retirement this week after 13 seasons in an emotional press conference.

In his "New Heights" podcast with his brother, Kansas City Chiefs' tight end Travis Kelce, Jason Kelce mentioned O'Pella and what he did for him ahead of his retirement announcement.

"One of the trainers with the Eagles has been battling cancer all season long and he's been there my entire career too -- Joe O'Pella. Thankfully, he's in remission," Kelce said.

"He wasn't able to tape me for any of the games this year, and he's taped my ankles my whole career, so he taped my ankles for the press conference one last time," Kelce confirmed. "So I had ankle tape on with sandals."

O'Pella concluded his lengthy social media post on Tuesday by congratulating Kelce on a storied career in the City of Brotherly Love, where Kelce spent his entire NFL career.

"Congratulations to the entire Kelce family on a Hall of Fame career on and off the field," O'Pella wrote. "To Kylie's husband; Wyatt, Elliotte, and Bennett's dad; the Eagles' center; Philadelphia's icon, and my brother: Jason, congratulations on retirement and here's to the future. I love ya."