Kyle Chalmers stuns at Olympics with 'mind-blowing' swim

Aussie swimming star Kyle Chalmers produced a remarkable 100m freestyle effort to catapult his team into a bronze medal place at the Tokyo Olympic Games.

Day 4 in the pool at Tokyo was action-packed with a number of Aussies collecting medals and the Aussie men did their best to add to the tally.

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Chalmers powered Australia into the 4x100m relay final after a brilliant anchor leg in the heats.

But the 2016 Rio gold medalist saved his best for the final after going even quicker in his 100m leg.

Chalmers clocked a remarkable time of 44.46 seconds, which Australian swimming legend Ian Thorpe said was the performance of the night in the men's relay.

His time was even faster than US star Caleb Dressel's 47.26 seconds.

“This (medal) was was not expected for us,” Thorpe said on Channel 7 commentary.

“This was for a bronze medal, but, gee, Kyle Chalmers loves the Olympics and loves to race. He loves to be set a task.”

Chalmers will be encouraged after the strong time heading into the 100m men's freestyle heats.

Ariarne Titmus delivers for Australia

But the best swim of the night came from Aussie superstar Ariarne Titmus.

The 20-year-old triumphed in a titanic final on Monday, defeating the United States' five-time Olympic champion Katie Ledecky.

Titmus' achievement is Australia's second gold medal of the Tokyo Games, following the women's 4x100m freestyle relay success.

And it delivers Ledecky, regarded as the greatest female swimmer ever, her first defeat in an Olympic final.

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