“We were texting towards the beginning of December when the Ravens were in a slump,” Murphy recounted. “He told me, “Coach, you always said that if I was going to hang it up, you would want to know when. I feel like this is the time.’”

But the Ravens had plenty of fight left in them to ensure that the careers of legendary linebacker Ray Lewis, who also retired this off-season, and Birk did not end with a whimper.

They began an improbable roll through the playoffs, eventually reaching Super Bowl XLVII, where they withstood a furious second-half comeback by San Francisco to hold on for a 34-31 triumph.

“That’s the way you want to end your career,” Birk remarked. “To be on a team that had what it takes and to be able to accomplish that goal in your last year—it’s like all the stars lined up right.”

But part of the Pro Bowler was not entirely sure whether to retire, and he didn’t make his final decision until the post-parade confetti had settled.

“Every year you re-evaluate how you feel, where your family is at,” he said. “I was torn a little bit, but I just followed my heart. I considered myself to be a blessed man and that it was time to move on.”

According to Murphy, the next stop for Birk will be the Harvard Athletic Hall of Fame, which he will enter this spring.

For now, Birk is a free man—free from grueling off-season training and free to spend time with his familyand has no regrets.

“I’m just going to pour my time and energy into my family right now,” he said. “I’m just fortunate to have played with so many great players. Being able to win the Super Bowl is as good as it gets and it’s a heck of a way to end my career.”

—Staff writer Justin C. Wong can be reached at justinwong@college.harvard.edu. Follow him on Twitter at @justincwong94.