Ariarne Titmus has taken down American champion Katie Ledecky in the 400m freestyle final at the Tokyo Olympics.
Ledecky is widely regarded as the greatest female swimmer of all time, having won five Olympic gold medals.
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But she was no match for the 20-year-old Titmus on Monday, the Aussie surging home to claim Australia's second gold medal of the 2021 Games.
"This is amazing," Ian Thorpe said in commentary for Channel 7.
Titmus had dethroned Ledecky at the 2019 world championships in a major boilover after the American won gold at the Rio Olympics in 2016.
"I can't believe it," Titmus told Channel 7 after the race.
The loss handed Ledecky her first defeat in an Olympic final.
In lane three, Titmus kept watch on Ledecky in lane four in what became the uttimate match race between the pair.
The American 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.
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.
Fans erupted on social media after the incredible Aussie triumph.
Holy cow!! What a race! Titmus beats Ledeckie in a nail-biter. Wow!
— Deb Spillane (@DebSpillane) July 26, 2021
— Aaron Eugol (@ajl247) July 26, 2021
I knew I shouldn’t have said anything.
Katie has met her match. What an incredible close by Titmus. Wow. https://t.co/8PShslj5rW
— Ethan Budowsky (@ethanbudowsky) July 26, 2021
Titmus with gold. Wohoo
— Sandeep Prasad (@prasad_sandeep) July 26, 2021
Aussies add two bronze medals
Earlier, Emma McKeon added a bronze medal to her incredible Olympics collection.
McKeon's 100m butterfly bronze on Monday follows her gold as part of Australia's triumphant 4x100m freestyle relay team.
McKeon produced a personal best of 55.72 seconds in a final won by Canadian Maggie MacNeil (55.59).
"To do a PB in an Olympic final, I'm pretty happy," McKeon said.
The Australian's butterfly bronze comes on a gruelling program in Tokyo which could reap seven medals for the Wollongong-born allrounder.
She's a genuine gold chance in both the individual 50m and 100m freestyles, with medal opportunities in three more relays.
Australia's 4x100m men's relay team then claimed bronze to cap off the Day 3 action.
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