INDIANAPOLIS (AP) — Andrew Luck watched one last game from the sideline Saturday.

Then he said goodbye to the NFL.

The Indianapolis Colts quarterback heard boos as he walked away from the field, then walked to the podium and made the surprise decision official. The oft-injured star is retiring at age 29.

“I’m in pain, I’m still in pain. It’s been four years of this pain, rehab cycle,” Luck said. “It’s a myriad of issues — calf strain, posterior ankle impingement, high ankle sprain. Part of my journey going forward will be figuring out how to feel better.”

Luck wasn’t planning to make the announcement following Saturday’s 27-17 loss to the Chicago Bears. But when ESPN first reported the news during the fourth quarter, Luck changed the plan for a Sunday afternoon announcement.

Instead, he held a 25-minute impromptu news conference.

At times he sounded wistful. At others, his voice cracked with emotion.

One thing was clear: The endless barrage of injuries stripped away his joy for the game and prompted him to walk away so he could enjoy the life he wants.

“There’s no doubt when you hear him talk about the cycle of pain and injury and rehab, you can hear that,” coach Frank Reich said. “There’s a saying in football that everyone knows and everybody lives by, it’s next man up and even though this situation is unique, no one is exempt.”

That task now falls to Jacoby Brissett, a fourth-year player whom the Colts acquired in a cutdown weekend trade two years ago.

He went 4-11 as a starter in the 2017 season after taking over for opening day starter Scott Tolzien.

But the Colts had already been preparing for the possibility Luck might not be ready for the Sept. 8 season opener against the Los Angeles Chargers. Luck was diagnosed with a strained left calf in March and team officials kept him out of all of the team’s offseason workouts.

He returned to limited action when training camp opened in late July. After three practices, though, the lingering pain near his ankle forced him back into rehab. He hadn’t practiced with the team since, though he did throw passes in pregame warmups before last week’s preseason game.