Veteran Olympian Eamon Sullivan said Australia's swimmers were "under-prepared" for the pressure they experienced at the London Olympics, contributing to the nation's worst medal haul in 20 years.

Australia won only one gold medal in the pool, in the women's 4x100m freestyle medley. It was the first time since 1976 that Australia failed to win a swimming gold in an individual event.

Sullivan, a former world champion, an Olympic silver medalist and for whom London was his third games, said many of the swimmers were taken aback by the intensity of the experience in London.