Mark Zaleski/Associated Press
In the century that it has grown into the nation’s most-watched sport, the N.F.L. has expected players to act like warriors willing to suck up the pain and sacrifice their bodies for the good of the team, and to be grateful they are paid handsomely to do it.
Yet even as awareness of the physical toll of the sport rises, the sudden retirement just two weeks before the start of the season by the Colts’ quarterback Andrew Luck at age 29 still provided a jolt.
Luck, a former first overall draft pick and one of the league’s brightest stars over the last seven seasons, said Saturday he could no longer take the years of pain and rehabilitation from a host of cringe-worthy injuries: a lacerated kidney, injured ribs, at least one concussion, torn cartilage in his throwing shoulder and, most recently, a calf and ankle injury.