Professional career A shooting guard since his amateur days with RFM-Swift Corporation of the
Philippine Basketball League, Agustin saw limited minutes during his rookie season with the grandslam-winning San Miguel Beermen in 1989, playing backup to his more illustrious teammates
Samboy Lim and Elmer Reyes. However, beginning the 1990 season, he became a regular part of the Beermen's backcourt rotation with the departure of Reyes to expansion team Pop-Cola (RFM) and constant injuries to Lim and
Hector Calma. He led the Beermen to three more titles in the early ‘90s, including All-Filipino championships in 1992 and 1994, this time as a starter and a star. Agustin was picked by
Yeng Guiao to play for the
Batang Red Bull Energizers during the
2000 expansion draft. He helped them win the
2001 Commissioner's Cup. In Game 6 of the
finals, he made two clutch free throws that sealed the championship. He retired from the PBA after that. For a time, he played semi-professional basketball as an import in Brunei.
Coaching career He is the former head coach of the
San Sebastian Golden Stags men's basketball team in the
NCAA, having taken over from
Jorge Gallent in 2009, and winning a championship in the same year. In 2010, he became head coach of his former PBA team, the
San Miguel Beermen. During the
2011 PBA Governors' Cup, Agustin steered the team (then known as the Petron Blaze Boosters) to the
championship, defeating the
Talk 'N Text Tropang Texters in seven games. He became the 9th coach in PBA history to win a title in his first year as head coach. On July 25, 2013,
San Miguel Corporation, owner of Petron Blaze Boosters and
Barangay Ginebra San Miguel, announced the appointment of Agustin as interim coach of Barangay Ginebra San Miguel for the
2013 PBA Governor's Cup. On January 5, 2015, Barangay Ginebra team manager
Alfrancis Chua announced during the team's practice the reappointment of Agustin as head coach of the team. This was after former coach
Jeffrey Cariaso's attempt to end Ginebra's PBA championship drought failed after two conferences. After a quarterfinal finish in the Commissioner's Cup, Agustin was fired as the head coach of Ginebra and was replaced by assistant coach
Frankie Lim. Following his termination, he returned to San Miguel Beermen as an assistant coach. == Political career ==