Aussie Mack Horton Refuses To Share Podium With Chinese Swimmer

Olympic gold medallist Mack Horton has been fighting with Chinese swimmer Sun Yang for at least three years now.

And the 23-year-old Aussie's latest protest has caused a sensation after the 400m freestyle final at the World Swimming Championships in Gwangju, South Korea, overnight.

Sun won last night's race, with Horton in the second place, making it four 400m freestyle World Championship victories in a row for the Chinese swimmer.

But after collecting his silver medal, the Aussie refused to take his place on the podium with Sun and Italian bronze medallist Gabriele Detti.

Horton later posed for photos alongside Detti, but not with Sun. When asked why he replied: "Frustration. I think you know in what respect."

It was a clear reference to Sun's drug-tainted past. In 2014, the Chinese swimmer was banned for three months by his own swimming body in China for testing positive to the stimulant trimetazidine.

Relations between Horton and Sun have been testy for years now. After the Rio Olympic final in 2016 -- when Horton beat Sun -- tensions between Australian and Chinese swimming authorities flared when Horton used the words "drug cheat" in relation to the man he had defeated.

The two have been fierce rivals since, and Sun is currently facing fresh allegations of violations of the doping rules -- over charges of smashing vials of his own blood with a hammer last year after a test.

Sun is seeking a public trial at the Court of Arbitration for Sport in September to defend himself. In the court of public opinion, many believe he has a lot to answer for.

Australian dual Olympian David McKeon was just one of many swimmers to signal his support for Horton using the hashtag #cleansport.

In other World Swimming Championships news, Aussie Ariarne Titmus has sensationally beaten American champ Katie Ledecky in the women's 400m final.

Ledecky, a five-time Olympic gold medallist who is still only 22, had not been beaten in any of her pet distances -- 400m, 800m or 1500m -- at any major international meet since the London 2012 Olympics.

More to come.