What happened: The Hall of Famer earned three Coach of the Year awards during a career that helped shape modern NBA offense. He spent 11 seasons with Boston and had his No. 19 retired in 1978.
Why it matters: Nelson became the only coach to surpass 1,000 wins after winning multiple championships as a player. His nearly five decades in the NBA stretched from the court to coaching and front-office roles.
By the numbers: Nelson's Boston championships came in 1966, 1968, 1969, 1974 and 1976. He appeared in 465 consecutive games.
What to watch: A celebration of life for Nelson is scheduled for Aug. 13 in Dallas.