On Sept. 15, 2012, Spencer Hagan came within a centimeter of losing his right leg.

Playing No. 3 Ohio State in a nationally televised game, the redshirt junior was thrust into duty due to a plethora of injuries to Cal’s tight end corps. And for a former walk-on who had shown flashes of potential in his first two seasons, there would be no better stage to launch what looked poised to be a breakout season. This was his shot to live his dream.

With four minutes remaining in the third quarter, Hagan lined up on the left side of the line, ran a hitch route and caught a quick strike from quarterback Zach Maynard. As he turned up field, he was immediately met by Buckeyes safety Christian Bryant. The crown of Bryant’s helmet ducked down and collided with his right knee, exploding through and gruesomely bending it in a way a knee should never bend. It became instantly clear to everyone watching that Hagan had sustained a major knee injury.

As he lay on the turf and clutched his right leg, the grim reality of his situation began to sink in. Hagan’s season was over before it really began. His chance at breaking out was all but gone.

“That was supposed to be my season to come out,” Hagan says.

An MRI would later confirm a torn ACL, MCL and meniscus. But it would also show damage to the exterior lining of his popliteal artery. Had the knee bent a few centimeters farther, the artery would have been severed, and his leg would have required amputation.

After reconstructive surgery in October, Hagan planned to go through rehab and come back to football. But he also began to realize that having been centimeters away from being an amputee had left him unable to look at football in the same light. Flashbacks from the injury lurked in the back of his mind, constantly reminding him of the horror that could have been. For the first time in his life, Hagan realized he wasn’t invincible.“It changed the way I see football, and it changed the way I see life,” he says. “Playing the game wasn’t as important as my health. I wanted my knee for the rest of my life.”

Last Tuesday, he officially announced his retirement from the game of football. While he wants nothing more than to continue to play the game he loves, he understands his body is not invincible. And while many players would feel conflicted about such a decision and would feel all kinds of frustration about being physically prevented from playing the game they love, Hagan has not had any second thoughts.

“Usually, guys are like, ‘I still wish I could play,’ ” he says. “I’m past that. I’m moving on from playing, and I’m enjoying where I’m at now, helping the guys and helping the coaches.”

Hagan will turn to a potential future of coaching, as he will continue working with the coaches as a team manager while he determines whether a future in coaching is where he belongs.

And although his career stats of 12 catches for 92 yards and a pair of touchdowns are just a fraction of what they could have been, Hagan has no regrets about packing up.

“I had the full experience at Cal,” Hagan says. “I walked on, earned a scholarship, scored a touchdown in the Big Game and got to play at Ohio State. All of the biggest college football things to do at Cal, I’ve done them all.”