Awkward slip of the tongue leaves Olympics presenter red-faced.

In a cringe-worthy slip of the tongue, a Channel Seven reporter has accidentally described a gold-medal-winning Chinese swimmer as a “cheat”.

Amanda Abate made the gaffe during Olympic coverage on Tuesday night while referring to comments made by 400m freestyle champion Mack Horton about his rival Sun Yang.

“Some big names of swimming are lining up to support Aussie gold medallist Mack Horton, with mounting backlash from China for calling one of its cheats, sorry, one of its stars a drug cheat,” Abate said.

Abate quickly apologised for her unfortunate slip-up during Tuesday’s broadcast, saying “I definitely didn’t mean that, but look everyone – it is a talking point.”

The controversy kicked off when Horton agreed his victory in the 400m was “a win for the good guys” during a post-race interview.

“Don’t know if it’s a rivalry between me and him, just me and athletes who have tested positive, I guess,” he said, referring to a question about Sun Yang.

Sun served a three-month suspension in 2014 after testing positive to a banned substance.

The tense war of words quickly escalated, with Horton attracting heated criticism in Chinese press, on social media and from the Chinese team over his comments.

“It is proof of a lack of good manners and upbringing,” team manager, Xu Qi, told China’s state-run news agency, Xinhua.

“We strongly demand an apology from this swimmer.”

But the Australian Olympic Committee has backed their man, saying he has a right to voice his opinion.

“Mack obviously has very strong views about the need for clean sport, as every single one of us does,” said Australia’s chef de mission, Kitty Chiller. “He has every right to express his views and his displeasure in that sense.

“We have no intention of making an apology.”

Mack Horton and Sun Yang will face off again for the 1500m freestyle event on the weekend.