Roberts was born in the UK, and with his family emigrated to Millicent, South Australia. In his late teens, the 199 cm ruckman was attracting interest from VFL clubs, but the new South Adelaide coach, Neil Kerley, persuaded Roberts to join the Club.
SANFL
Roberts joined South Adelaide in 1964 and debuted the following year. He learnt the craft of being a ruckman from his teammate and coach Neil Kerley.
WAFL
Robert spent four seasons with East Fremantle; it included being selected in the Western Australian state team in 1969.
VFL
Richmond enticed him to Victoria, where he played from 1971–1975, and he was a premiership player in 1973 and 1974. He also represented Victoria in interstate games.
Roberts was part of the John Pitura trade in which Pitura went to Richmond in exchange for Roberts, Francis Jackson and Graham Teasdale. In the 15 games he played with South Melbourne, he caught the attention of the umpires and was second in the Brownlow Medal.
In the 1976 pre-season, he had a disagreement with coach Ian Stewart and walked out on South Melbourne.[citation needed]
Roberts was a publican and for many years had a hotel in South Melbourne. "Have a ale with the Whale" was his motto. In the 1990s, he took over the licensee of the Duke of Wellington Hotel in Flinders St. Additionally, he wrote newspaper columns and did radio football commentary.
Victoria (VFL) 16.23 (119) defeated South Australia 7.9 (51), at North Hobart Oval, 11 June 1966, crowd: 23,764 Western Australia 13.11 (89) defeated South Australia 10.14 (74), at North Hobart Oval, 13 June 1966, crowd: 13,969 South Australia 21.20 (146) defeated Victoria (VFA) 9.11 (65), at North Hobart Oval, 16 June 1966, crowd: 10,199 South Australia 14.7 (91) defeated Tasmania 9.13 (67), at North Hobart Oval, 18 June 1966, crowd: 23,368