Swimming at the 1968 Ciudad de México Summer Games:

Dutchwoman [Ada Kok] had finished second in this event in 1964, was the 1966 European Champion, and had held the world record since 1965. Australian put forward the unknown [Lyn McClements] who had been a freestyler until the Olympic year and had never won a butterfly race until the Australian Trials in February 1968. American [Ellie Daniel] had won the 1967 Pan American Games and the 1968 US Olympic Trials and was expected to contend. McClements started the final quickly, leading by half a body length at the turn over American [Susan Shields], with Kok in third and Daniel fourth. McClements hung on over the last lap and won a surprise gold medal, with Daniel moving up for silver and Shields taking bronze, Kok finishing fourth.