Former NBA champion and Sixth Man of the Year Leandro Barbosa announced his retirement Monday and said he is rejoining the Golden State Warriors as a "player mentor coach." Barbosa, 37, played 14 NBA seasons with five teams from 2003-17 before returning to his native Brazil to continue his playing career. A first-round pick (28th overall) in the 2003 NBA Draft, he won Sixth Man honors with the Phoenix Suns in 2006-07 and helped the Warriors win the NBA championship in 2014-15.