A swimming world record has been broken at the Commonwealth Games trials on the Gold Coast — by a 99-year-old Australian man.

George Corones, who turns 100 in April, completed the 50-metre freestyle swim in 56.12 seconds.

Corones — the only swimmer in his 100-104 age group — swam alone.

The Australian Dolphins Swim Team posted on their Facebook page:

"We have just witnessed history in the making!"

George Corones has always enjoyed swimming. ( Facebook: Australian Dolphins Swim Team )

Although he has always been a keen swimmer, Corones only took it up seriously when he turned 80.

He first started swimming while attending primary school in Charleville, and continued to swim in high school and university, before taking about six decades off.

"The war stopped things, and from then until I retired at 80, I didn't swim at all competitively," he told the ABC in 2013.