As a player at Pitt he led the team to two consecutive post season tournaments in 1963 and 1964. He then served 12 years (1964–1975) as an assistant coach and head of recruiting under Timmons and Ridl. He helped to develop Pitt's famous amoeba defense that along with the superlative play of All-American forward Billy Knight launched a 22-game win streak for Pitt in the 1973-1974 season under Head Coach 'Buzz' Ridl. That carried Pitt to the Elite 8 that year, it's furthest advance in the NCAA tournament since making the Final Four in 1941. The '74 season ended in losing to eventual NCAA Champion, North Carolina State with David Thompson and Tom Burleson in a game played on NC State's home court in Raleigh.
After Ridl retired several seasons later, Grgurich was named Head Coach at Pitt for the 1975-1976 season and after two rebuilding seasons coached Pitt to 3 consecutive winning seasons in 5 total season as Head Coach at Pitt and a post season bid in 1980. Grgurich finished with close to a .500 record at Pitt at 69 wins and 70 losses as his mostly undermanned teams were noted with playing with high energy and enthusiasm and interesting defensive schemes employed by Grgurich.
He continued those defensive stratagems while the top asst.coach at UNLV, culminating with winning the NCAA championship in 1990 in destroying top ranked Duke and being #1 for all of 1991 and again reaching the Final 4 that year. He has served as an assistant coach for several NBA teams including extended stays with the Seattle SuperSonics under fellow Pittsburgher Head Coach George Karl, that reached the NBA finals in 1996. Seattle's teams were noted for their defensive prowess which were implemented by Grgurich with Karl's consent. Grgurich also was an asst.coach with the Portland Trail Blazers and the Denver Nuggets, again under Head Coach George Karl. Grgurich has been the highest paid assistant in the NBA for several seasons being sought after for his trusted knowledge of the game and his vast defensive coaching abilities and the enthusiasm he brings to the game. Considered by many as one of the best NBA asst. coaches ever.
National champion Postseason invitational champion Conference regular season champion Conference regular season and conference tournament champion Division regular season champion Division regular season and conference tournament champion Conference tournament champion