Caeleb Dressel won his fifth gold medal of Tokyo 2020 ©Getty Images

Caeleb Dressel and Emma McKeon continued their superb Olympic Games in the swimming pool as both bagged two more gold medals on the last day of finals.

The pair both tasted glory in their respective 50 metre freestyle events before adding to their hauls in the 4x100m medley relays.

American Dressel will leave Tokyo 2020 with five gold medals, taking his total haul to seven after two titles at Rio 2016.

He joins fellow greats Michael Phelps, Mark Spitz and Matt Biondi as United States swimmers who have topped the podium five times at a single Games, with his double here adding to his 100m freestyle, 100m butterfly and 4x100m freestyle successes.

His winning time over one length of the pool today was 21.07sec - an Olympic record.

Silver went to London 2012 champion Florent Manaudou of France in 21.55 and bronze was won by Bruno Fratus of Brazil in 21.57.

"I had a good feel throughout the race that I was ahead, I could see in my peripheral so it was exciting coming into the wall," said the 24-year-old Dressel.

"I was about 90 per cent sure, I didn't know if anyone in the outside lanes had me.

"It's very surreal, I'm trying to take it all in.

"All of Tokyo 2020, the Rings, and being on the podium.

"I'm trying to take everything in as much as I can.

"It's all over now. 

"A lot of parts of this meet really were not that enjoyable if I'm being quite honest.

"More parts are not enjoyable than enjoyable but the highs are very, very high."

Emma McKeon is now Australia's most decorated Olympian ©Getty Images
Emma McKeon is now Australia's most decorated Olympian ©Getty Images

McKeon has become Australia's most decorated Olympian with 10 medals - and the 27-year-old will take home a magnificent seven from Tokyo 2020.

She previously won gold in the 100m freestyle and 4x100m freestyle before today's double, as well as bronzes in the 100m butterfly, 4x200m freestyle and 4x100m mixed medley.

The 27-year-old has also matched Soviet gymnast Maria Gorokhovskaya's record for the most medals won by a female athlete at a single Games.

She has now won five Olympic golds after claiming the 4x100m freestyle title at Rio 2016, and won today's 50m race in an Olympic record of 23.81.

Sweden's world record holder Sarah Sjöström won silver in 24.07 and Denmark's Pernille Blume took bronze in 24.21.

"I never thought I'd win two gold medals in one session," McKeon said.

"I look at the athletes who have come before me and been so impressed with what they have done and been inspired by what they have done, but I've never really looked at the stats of medal counts. 

"It is an honour because I know I've worked so hard for it."

In the relays, Dressel recorded the fastest butterfly split in history to take the title away from Britain who had powered into the lead thanks to double Tokyo 2020 champion Adam Peaty's fantastic breaststroke leg - which was again the quickest ever recorded.

The US, also featuring Ryan Murphy, Michael Andrew and Zach Apple, ended in a time of 3min 26.78sec.

Britain ended in 3:27.51, a European record, as their swimmer Duncan Scott became the first athlete from the country in any sport to win four medals at a single Olympics, thanks to his haul of one gold and three silvers.

Italy won bronze in 3:29.17.

The American men's 4x100m medley relay team won gold with a new world record ©Getty Images
The American men's 4x100m medley relay team won gold with a new world record ©Getty Images

In the women's 4x100m medley relay, a straight fight between Australia and the US went the way of McKeon's team as Cate Campbell came powering past Abbey Weitzeil in the final metres.

Australia, also featuring double Tokyo 2020 backstroke champion Kaylee McKeown and Chelsea Hodges, won in an Olympic record time of 3:51.60.

The US clocked 3:51.73 and Canada won bronze in 3:52.60.

Canadian swimmer Penny Oleksiak became her country's most decorated Olympian by winning her seventh medal.

On a day of history, American Bobby Finke won the men's 1500m freestyle to add to his 800m crown.

In a close race, German Florian Wellbrock led going into the final turn but Finke, as he did in the 800m, produced a superb late surge.

He won in 14:39.65 as Ukraine's Mykhailo Romanchuk took silver in 14:40.66.

Wellbrock faded and had to make do with bronze in 14:40.91.

The US end the Tokyo 2020 swimming competition with 30 medals - 11 of them gold.

Australia won 20 medals with nine golds, as the two nations dominated the sport.