It was McKeon's seventh medal in Tokyo

TOKYO (AFP) - Emma McKeon made Olympic history Sunday in helping Australia upset two-time defending champions the United States to soar to the women’s 4x100m relay gold medal Sunday.

Their team of Kaylee McKeown, Chelsea Hodges, McKeon, and Cate Campbell touched in a new Olympic record 3mins 51.60secs ahead of the US in 3:51.73 and Canada in 3:52.60.

It was McKeon’s seventh medal in Tokyo, a feat no other female swimmer has ever achieved at a single Olympics.

Canada’s Kylie Masse was fastest through the opening backstroke leg before teenager Lydia Jacoby put the Americans in front following the breaststroke.

A blistering butterfly swim from McKeon closed the gap on the two teams, leaving veteran Campbell to produce a devastating final 100m to reel in US freestyler Abbey Weitzeil and win gold.

It was 27-year-old McKeon’s fourth gold in Tokyo to go with her three bronze, overtaking East German Kristin Otto’s six medal-haul in 1952 which was matched by American Natalie Coughlin in 2008.