Career
Dempsey made his debut for Footscray in 1967. In 1969, he spent six weeks in hospital after being burnt by a bushfire near his home in Truganina and was told he would never play football again. He played out his career at the Kangaroos, playing 122 games for them, and retired in 1984.
Dempsey was named an emergency in the Kangaroos Team of the Century.
In 1996 Dempsey was inducted into the Australian Football Hall of Fame. He was named as first ruckman in the Footscray"s Team of the Century.
Player honours:
Brownlow Medal 1975
Runner-up Brownlow Medal 1970
Most ever Brownlow votes
Footscray best and fairest 1970, 1973, 1974, 1975, 1976, 1977
North Melbourne best and fairest 1979
Footscray captain 1971-1972, 1977–1978
Footscray/Western Bulldogs Team of the Century
North Melbourne/Kangaroos Team of the Century
All-Australian 1972
Victorian representative (22 games, 8 goals)
Represented Australia in "The Galahs" Australian Football World Tour 1968. Dempsey was appointed Specialist Ruck Coach of the Carlton Football Club at the end of the 2005 season.