Bob was the first St Georges rower to represent New Zealand for the Colts in Australia in 1970. Bob rowed in the Senior Eight for St Georges in 1971/72.
In 1969 after leaving school a group of young men including Ross McKee, Rob McCarthy and Rex Potter moved to row out of St Georges Rowing Club. The attraction to St Georges was the success of Maiden eight coached by Barry Leitch in 1966/67. Bob was in the Senior (Premiere) eight in 1971/72. As he had represented New Zealand he was not able to compete in the Junior Eight. The crews for the Junior and Senior eight were the same except Bob Murphy replaced Dennis Delaney in the Senior Eight.
He joined Grant McAuley at Whakatane Rowing Club in 1973, his first year was impacted when he caught rheumatic fever. In 1974/75 Grant McAuley and Bob Murphy together won the NZ Championships Coxed Pairs, when they were members of Whakatane NZ Championship winning Senior Eight and won subsequent NZ selection.
He is Athlete 361 for representing New Zealand at the 1976 Summer Olympics in the coxless four in a team with David Lindstrom, Grant McAuley, and Des Lock, narrowly beaten by the team from the Soviet Union to fourth place.