When wide receiver Christian Kirk went down on the first offensive play of the game for the Jacksonville Jaguars in Week 13, it wasn’t immediately clear what went wrong.

With no Cincinnati Bengals players around him, Kirk hauled in a 26-yard reception and stayed down on the field.

While the Jaguars initially called it a groin injury for Kirk, head coach Doug Pederson later called it a core muscle injury that required surgery to repair. Four weeks later, Kirk made his return to practice Wednesday and told reporters about the injury that sent him to injured reserve.

“These core muscle injuries, they can kind of have a broad spectrum of severity,” Kirk said, via Demetrius Harvey of the Florida Times-Union. “Mine was my left adductor, left ab off the bone, and then I had a right tear of my abdominal that I’d been playing with since Week 6. So I had been running on an injured groin for a while and the day that it went, it was time for it go.”

Kirk, 27, led the Jaguars in receiving yards at the time of his injury with 787. Last season, he led the team in receptions (84), receiving yards (1,104), and touchdown receptions (eight).

Story originally appeared on Jaguars Wire