Phillip Louis Mathews was born in Riverside, California and graduated from John W. North High School in Riverside in 1968. Mathews then attended Riverside City College for two years and transferred to the University of California, Irvine and lettered two years as a guard on the UC Irvine Anteaters men's basketball team. Mathews graduated from UC Irvine in 1972 with a B.A. in comparative cultures.
Coaching career
Mathews began his coaching career in the 1972–73 season as an assistant at UC Irvine under Tim Tift. He then spent one season as junior varsity coach at Santa Ana Valley High School before returning to UC Irvine for four more seasons as an assistant again under Tift. UC Irvine, then in Division II, made the 1974 NCAA Tournament. In 1978, Mathews returned to Santa Ana Valley High to become varsity basketball coach. In three seasons with Mathews as coach, Santa Ana Valley won two Century League titles. In 1981, Mathews returned to the collegiate ranks in his first NCAA Division I job, as an assistant coach at Cal State Fullerton under George McQuarn. During Mathews's four seasons on staff, Cal State Fullerton made the 1983 National Invitation Tournament. From 1985 to 1995, Mathews was head coach on the junior college level, at Ventura College. Mathews had a 298–56 record at Ventura, with CCCAA titles in 1987 and 1995. Mathews also served as athletics coordinator at Ventura in the 1994–95 season. Mathews then was head coach at the University of San Francisco from 1995 to 2004. San Francisco had winning records in 6 of Mathews's nine seasons and made the 1998 NCAA Tournament by virtue of winning the WCC Tournament. After the 2003–04 season, USF fired Mathews, who finished his tenure with a 139–123 record. After USF, Mathews returned to the junior college ranks as head coach at San Bernardino Valley College. Mathews led San Bernardino Valley to a 27–5 record in 2004–05 with the Foothill Conference title, then 24–12 in 2005–06. In 2006, Mathews returned to Division I as an assistant coach at Nebraska under Doc Sadler. Mathews remained on staff for four seasons, during which Nebraska made the NIT in 2008 and 2009. In 2010, Mathews joined Ben Howland's staff at UCLA as an assistant coach. Mathews coached for three seasons, during which UCLA made the NCAA Tournament in 2011 and 2013 and won the Pac-12regular season title in 2013. Mathews became head coach at Riverside City College in 2013. Riverside went 12–17 in 2013–14, then 10–17 in 2014–15.