Complex sentence: Robertson debuted with South Melbourne at the age of 18 and played for the club between 1927 and 1937, during which time he was also a world champion professional sprinter, winning the world title in 1930.
Split into simpler sentences: Robertson debuted with South Melbourne at the age of 18 and played for the club between 1927 and 1937. While at South Melbourne, he was also a world champion professional sprinter, winning the world title in 1930.