[2] 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.

[4] Agustin was picked by Yeng Guiao to play for the Batang Red Bull Energizers during the 2000 expansion draft.

[6] 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.

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.

[10] This was after former coach Jeffrey Cariaso's attempt to end Ginebra's PBA championship drought failed after two conferences.