Rob started rowing in 1965/66 from Waitemata Rowing Club where he had rowed as a Tamaki College school boy and he joined St Georges Rowing Club in 1969. He was a crew member in the successful St Georges Junior and Senior Eight and was selected as reserve for the 1972 Olympic Rowing team.
The 1971/72 AGM minutes acknowledged Rob “…on being selected both for the NZ Colts Team and competed in Australia earlier this year and for his selection in the 1972 Olympic Rowing Team.” Rob McCarthy was a travelling reserve for the gold medal winning Olympic eight in 1972. In 1973/74 Rob McCarthy won the Maiden doubles title at the NZ Championships.