Paul Douglas Westphal (born November 30, 1950) is a retired American basketball player and a former head coach with several National Basketball Association (NBA) and college teams. Westphal has had a storied career in the NBA, both as a player and as a coach. As a player, he won an NBA championship with the Boston Celtics in the 1974 NBA Finals. In addition to being a five-time All-Star selection, from 1977 to 1981, Westphal earned three All-NBA First Team selections and one Second Team honor. Later, he returned to the Finals in 1993 as head coach of the Phoenix Suns. He returned to his home state of California when he was the men's basketball head coach at Pepperdine University from 2001 to 2006.
Westphal is currently an assistant coach on Lionel Hollins' staff on the Brooklyn Nets.
Westphal was born in Torrance, California. He went to Aviation High School and then USC. He was the 10th overall pick in the 1972 NBA Draft by the Boston Celtics. After three seasons in Boston, including a championship ring in 1974, he was traded to the Phoenix Suns. In 1976, Westphal helped the Suns reach their first-ever Finals appearance, where they played the Celtics. Game 5 of that series is often called "the greatest game ever played" in NBA history.