Tokyo, Aug 1 : Australian Emma McKeon's success in the pool left the world in awe of the 27-year-old athlete on Sunday as she became the most successful swimmer from her country at the Olympics, winning a whopping seven medals, including four gold and three bronze, in Tokyo. On Sunday, at the Tokyo Aquatics Centre, Emma first beat world record holder Sarah Sjoestroem of Sweden in the women's 50m freestyle final, sprinting to a 23.81-second finish to clinch gold and later in the day helped the team edge defending champions the United States for the women's 4x100m medley relay gold. Kaylee McKeown, Chelsea Hodges, Emma McKeon and Cate Campbell concerted their efforts to win Australia's third Olympic gold in the event in 3:51.60, a new Olympic record. With the two gold medals on Sunday, Emma propelled her country to 20 medals overall -- nine of them gold -- which is their best performance ever in the Olympic pool. Emma's list of achievements in Tokyo include gold in 100m freestyle, 4x100m freestyle relay, 4x100m medley relay and women's 50m freestyle, while she also won three bronze -- in mixed 4x100m medley relay, 100m butterfly and 4x200m freestyle relay. Australia's nine gold in Tokyo is one better than Melbourne 1956 and in terms of individual medals won, they pushed their total up to 20, equalling the performance of the 2008 Beijing Olympic Games. Emma not only became the greatest medal winner in Australian Olympic history, surpassing Ian Thorpe and Leisel Jones, but the first Australian ever to win four gold at a single Olympics. If one includes her 2016 Rio Olympics relay gold, she joins Thorpe as the only Australian ever to win five career gold. Emma's two gold on Sunday elevated her to 11 medals in Olympic history, making her the greatest non-American swimmer of all time in Olympic history and the greatest female swimmer ever at a single Games, according to the Australian Olympic Committee (AOC). "Only Americans rank above her on career medals -- Michael Phelps (28), Jenny Thompson, Ryan Lochte, Dara Torres and Natalie Coughlin with 12. She has drawn level with the greatest swimmers of their day, Mark Spitz and Matt Biondi with 11. And just remember that the American depth runs so constantly deep through the sport that every relay those swimmers contested carried an almost certain gold, at worst a silver or bronze," said the AOC website. "I can't believe the week I've had. I never thought I would win the 50m freestyle. I had trained for the 200m instead (the only event she cut from her programme to make it more manageable). But when I went out there this morning, I had the belief I could win," said Emma. "It is very surreal. The whole week I have been keeping my emotions at a certain level. I don't usually say this but I wanted to win here." /IANS