Chinese state-run media has hit back at Australian Olympic gold medallist Mack Horton and his country after he called their homegrown star Sun Yang a drug cheat.

The Global Times newspaper labelled swimmer Horton "immoral" and described Australia as a former "offshore prison".

Horton, 20, beat defending Olympic champion Yang to the gold medal in the 400m freestyle in Rio, causing the Chinese athlete to break down in tears.

The row had started in the build-up to Saturday's final, when Yang splashed water in the face of Horton during a training session at the Olympic aquatic centre.

Asked about it, Horton said Yang "splashed me to say hello, and I didn't respond because I don't have time for drug cheats".


Yang served a drugs suspension in secret in 2014, but Horton's comments still caused outrage in China, both online and in print.

Image: Mack Horton stood by his comments, but has been vilified in China

The Global Times is close to the ruling Communist Party, meaning its opinion piece was likely sanctioned at the highest levels of government.

The article criticised Horton's "cynical smugness" and said Australia should be embarrassed by the swimmer's "disgraceful" victory.

It also referenced Australia's "early history as Britain's offshore prison".

"In many serious essays written by Westerners, Australia is mentioned as a country at the fringes of civilisation.

"This suggests that no one should be surprised at uncivilised acts emanating from the country."

In Rio, Chinese journalists confronted Horton, asking him why he had used the terminology.

He replied: "I used the word drugs cheat because he tested positive."

The hashtag #SunYangDontCry also started trending in China, and a video of Yang sobbing was widely shared.

The Australian Olympic Committee is standing by Horton, saying he is allowed to express himself.

Horton and Yang will face each other again in the men's 1,500m freestyle event on Sunday.