ENGLEWOOD, CO - MARCH 07: Quarterback Peyton Manning addresses the media as he announces his retirement from the NFL at the UCHealth Training Center on March 7, 2016 in Englewood, Colorado. Manning, who played for both the Indianapolis Colts and Denver Broncos in a career which spanned 18 years, is the NFL's all-time leader in passing touchdowns (539), passing yards (71,940) and tied for regular season QB wins (186). Manning played his final game last month as the winning quarterback in Super Bowl 50 in which the Broncos defeated the Carolina Panthers, earning Manning his second Super Bowl title. (Photo by Doug Pensinger/Getty Images)

ENGLEWOOD, CO - MARCH 07:  Quarterback Peyton Manning addresses the media as he announces his retirement from the NFL at the UCHealth Training Center on March 7, 2016 in Englewood, Colorado. Manning, who played for both the Indianapolis Colts and Denver Broncos in a career which spanned 18 years, is the NFL's all-time leader in passing touchdowns (539), passing yards (71,940) and tied for regular season QB wins (186). Manning played his final game last month as the winning quarterback in Super Bowl 50 in which the Broncos defeated the Carolina Panthers, earning Manning his second Super Bowl title.  (Photo by Doug Pensinger/Getty Images)