Ken Lock first came to prominence in 1931 playing A Grade with the Fairfield Club. He then played in the Southern Districts A Grade Inter District competition but did not make his Grade debut until 1936.
Ken was a loyal servant of the Fairfield Rugby League Club, remaining with them when they withdrew from the Southern Districts Junior Rugby League to play in the Metropolitan competition in 1933 and 1934. Ken also played with the local side while he was playing with Wests.