I understand why Andrew Luck retired, because I've been in his shoes
Indianapolis Colts QB Andrew Luck Is Retiring From the NFL. Yes, Really - The Ringer
Luke Kuechly Joins N.F.L.'s Under-30 Retirees Club - The New York Times
Colts quarterback Andrew Luck retires from NFL - CBS News
Patriots' Tom Brady reflects on Andrew Luck retiring: 'It's his life'
Andrew Luck retirement: Colts QB to end NFL career - Sports Illustrated
Colts QB Andrew Luck Retired. His Legacy Lies in What Could Have Been. - The Ringer
Former NFL Players Show Why Andrew Luck's Retirement Isn't a Surprise
Oft-injured Colts QB Andrew Luck, 29, announces retirement