Manning's retirement wouldn't come as a shock. The soon-to-be 40-year-old is the oldest quarterback ever to start a Super Bowl.
After the Broncos won the national championship, on-field cameras caught Manning telling Pats coach Bill Belichick, "This might be my last rodeo."
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Manning will exit as the NFL's all-time leader in passing yards, passing touchdowns and total wins as a quarterback.
But Manning's postseason legacy has always been a point of criticism, which made his team's Super Bowl win that much more important. Manning now has two Super Bowl rings after Denver's victory.
There's a reason Manning waited until after the season was over to make this decision. Manning said at Super Bowl Opening Night he didn't want a farewell tour throughout an entire season.
And just because Manning might be retiring from playing doesn't necessarily mean he's done with football.
There's speculation he could consider a front office job, with one report from CBS highlighting Cleveland and Tennessee as possible landing spots.
"Few have left their marks on a sport as Peyton Manning has," Indianapolis Colts owner and CEO Jim Irsay said in a statement. "Simply put, he revolutionized NFL football. Peyton energized it as had no one before him, he made it more fun for our fans and (he) made the game better. Off the field, Peyton has been a tremendous ambassador for the game and the epitome of someone who gives back to the community. He is the most recognizable face in the history of the NFL and perhaps its most popular. I will miss seeing #18 on the field on Sundays, and I am proud and thankful for all he's done for the Colts, our community and the NFL. On behalf of Colts and NFL fans worldwide, I thank Peyton and congratulate him on an incredible career."
Manning played for the Colts for 14 seasons between 1998 and 2011. He began playing for the Broncos in 2012.
Congratulations Peyton, on an incredible career. You changed the game forever and made everyone around you better. It's been an honor.Posted by Tom Brady on Sunday, March 6, 2016