Don Nelson, the second-winningest coach in NBA history who won five championships as a player with the Boston Celtics, died Sunday. Nelson’s death was announced by the Golden State Warriors, one of the teams he coached. “Don Nelson was a true innovator whose influence on the game of basketball is still felt today,” current Warriors coach Steve Kerr said. In his final season as a coach, Nelson mentored rookie Stephen Curry in 2009-10. “He taught me a lot during our one season together and I’ll never forget the night he became the winningest coach in NBA history in Minnesota.