One of the most heralded shooters of his time, Ray Allen announced his retirement from the NBA Tuesday via The Player's Tribune. The two-time NBA champion wrote an open letter to his 13-year-old self, which included some of the wisdom he learned throughout the next 28 years of his life. Allen retires after 19 season with career averages of 19 points, 40 percent three-point shooting, four rebounds and three assists. The UConn alum won NBA titles in 2008 and 2013 with the Celtics and Heat, respectively.