Denver Broncos' Peyton Manning bid an emotional farewell to the NFL after 18 seasons and said he had "no regrets".
The Broncos confirmed the veteran quarterback's decision to retire on Sunday and Manning held a media conference a day later to reflect on a glorious career.
"There's just something about 18. Eighteen's a good number ... and today I retire from football," an evidently emotional Manning said.
The 39-year-old bowed out with a 24-10 victory over Carolina Panthers at last month's Super Bowl 50 - his second triumph in the sport's showcase event, making him the first starting quarterback to win the crown with two different franchises, having prevailed with the Indianapolis Colts in Super Bowl XLI.
Despite enduring his worst campaign as a professional this season, with injuries taking their toll, Manning will retire as the league's all-time leader in passing yards (71,940), passing touchdowns (539) and quarterback wins (186, tied with Brett Favre).
He also boasts five NFL MVP awards and 14 Pro Bowl selections during his career.
"I revere football, I love the game," he added. "So you don't have to wonder if I'll miss it. Absolutely, absolutely I will miss it."
Manning offered glowing praise to the Broncos, who he joined in 2012 after 14 seasons with the Colts, but is confident the timing of his decision is wise and is looking forward to the future.
"Grateful is the word that comes to my mind when thinking of the Denver Broncos," he added.
"To all of my Denver team-mates, thank you for what you've done for this old quarterback. And of course my gratitude to the Broncos fans everywhere ... football fans everywhere need to know how much they've meant to me over the years.
"I'm totally convinced that the end of my football career is just the beginning of something I haven't discovered yet. Life is not shrinking for me. It's morphing into a whole new world of possibilities.
"I have no regrets. I have fought the good fight. And after 18 years, it's time. God bless all of you and God bless football."
Denver general manager and former Broncos great John Elway marvelled at Manning's remarkable career and noted how he changed the sport during his time on the field.
"Peyton Manning revolutionised the game," Elway said. "There's not a guy in the NFL who can walk away and say, 'I have done everything that can possibly be done at quarterback.' Peyton can do that."