The greatest basketball player in Grant High School history, Arenas was an All-LA City Basketball choice in 1998 and 1999. He then attended the University of Arizona, where he was an All-Pac 10 selection in 2000 and 2001. He led the Wildcats to the 2001 NCAA championship game. Joining the NBA following his sophomore year when he was drafted with the 31st pick by Golden State, he played for four NBA teams from 2001-12.

Arenas was named the NBA Most Improved Player in the 2002–03 season. His finest years were in Washington where he was a three-time All-Star (2005, 2006, 2007). He was an All-NBA second team selection in 2007 when he averaged 28.4 ppg. He once scored 60 points against the Lakers breaking the all-time Washington franchise mark. The 6-4 Arenas ended his NBA career with 11,402 points scored and a 20.7 per game career scoring average. He was inducted in 2017 into the Los Angeles City Athletics HOF. Today he runs his own production company.