According to ESPN's Chris Mortensen, the team will announce the release of the four-time league MVP at a news conference. Cutting him will prevent a $28 million cap hit for the team and instantly make Manning the most coveted free agent since Reggie White.
Manning underwent multiple surgeries to fuse vertebrae in his neck over the past 19 months. He missed the entire 2011 season.
The move has been in the works ever since it became apparent that the Colts would be in a position to draft Stanford quarterback Andrew Luck. Still, as recently as seven months ago, Manning being released by the Colts would have been unthinkable.
He was the face of the Indianapolis Colts franchise, the man who resurrected a team that spent most of its 13 previous years in the city as an NFL also-ran. Indy landed the No. 1 pick of the 1998 draft and used it to take Archie Manning's son, a football player pegged for greatness ever since he stepped on a high school field.
Peyton ended up becoming the rare savior who lived up to expectations. He had the team in the playoffs in 1999 and only missed out on the postseason once in the next 10 seasons. Manning won four league MVPs and led the Indianapolis version of the Colts to their only Super Bowl win at the end of the 2006 season.
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Provided he's able to play, Manning will attract unprecedented attention in the free-agent market.
Meanwhile, Andrew Luck will have two roles to play in Indianapolis. He'll have to be the franchise's next superstar -- while, at the same time, replacing a true legend.
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