'Class': Katie Ledecky's incredible act after Ariarne Titmus gold

Ariarne Titmus and Katie Ledecky have been praised for their incredible sportsmanship after the Australian took down the American champion at the Tokyo Olympics.

Titmus won gold in the 400m freestyle final on Monday, beating Ledecky in an incredible finish.

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The American, a five-time Olympic champion, held the lead for the initial 300m but Titmus was watching her all the way, literally lurking at her heels.

The young Australian ominously surged closer and was just 0.16 seconds behind Ledecky with 100m remaining.

Titmus then reeled in her rival in a perfectly-executed race plan to win by half a body-length in a time of three minutes 56.69 seconds.

The loss delivered Ledecky her first at the Olympic Games after Titmus also won the event at the 2019 world championships.

But despite the devastation, Ledecky showed her absolute class in the moments after the race.

The American could be seen congratulating Titmus and laughing at the Australian's reaction after touching the wall.

The fierce rivals then put their arms around each other on the pool deck in a beautiful moment of sportsmanship.

“I thanked her. I wouldn't be here without her," Ledecky said of her post-race exchange with Titmus.

"She set this incredible standard. All credit to her for the swimmer she is. I've been trying to chase her.

"Really exciting now we have this battle going. It's really fun to race. So, yeah, that's the best part about it.

"The race I tried to stay as composed as I could, then just tried to stick to my race plan. I can't believe I pulled it off.”

Fans flocked to social media to praise Ledecky and Titmus for their sportsmanship.

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

Ledecky touched home in 3:57.36 and China's Li Bingjie was well back in third position in 4:01.08.

Titmus and Ledecky will also square off in a much-hyped 200m freestyle battle, though the American is favoured to win their duel over 800m.

“I can't believe it. I'm trying to contain my emotions," Titmus said.

"I have the 200m (freestyle) tonight. Oh my gosh. I can't believe it.

"This past year I don't know whether it's gone fast or slow, but to get here was a relief.

"To come here and do the job. I'm over the moon.”

Australia added two bronze medals in swimming on Monday - Emma McKeon in the 100m butterfly and the men's 4x100m freestyle relay team.

with AAP

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