Ariarne Titmus' "proud" parents couldn't contain their emotions after the 20-year-old held off one of the greatest female swimmers of all time, to claim gold in the 400m freestyle at the Tokyo Olympics.
Titmus triumphed in a titanic final on Monday, defeating the United States' five-time Olympic champion Ledecky after touching first in a time of three minutes 56.69 seconds.
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Titmus' achievement is Australia's second gold medal of the Tokyo Games, following the women's 4x100m freestyle relay success.
And it delivered Ledecky, one of swimming's greatest ever female athletes, her first defeat in an Olympic final.
Emotions in Titmus' camp were running high, as evidenced by the reaction of her coach Dean Boxall, who celebrated the victory like a man possessed.
The 20-year-old's parents sadly couldn't be in Tokyo to celebrate with their daughter because of Covid-19, but they were watching from Noosa alongside Aussie Olympic great Dawn Fraser.
Footage showed Titmus' mum Robyn, dad Steve and younger sister Mia all cheering on the star as she became the toast of a nation.
The Tasmanian-born swimmer's dad could be seen wiping back tears in a heartwarming reaction to his daughter's incredible performance.
"I can’t believe it," a teary Steve Titmus said in the moments after the race.
“I’ve lost my voice. I cannot believe it. Wow. Unbelievable. Just quite extraordinary. She’s done it. She’s actually done it. Wow."
Mum Robyn added: “God she can race. I’m just so proud of her. That 100m, the last hundred. God she can race."
Titmus was clearly over the moon after realising her Olympic dream and jokingly said that she suspected the performance would have brought a tear to her dad's eyes.
“My mum is the most competitive person I know. I get this competitiveness from her. But, yeah, I know that dad would be probably crying, he’s a bit of a softie,” she said.
“I just want to thank them for everything. None of this would be possible without them. Moving to Brisbane to train. Not just my parents, my sister, my boyfriend, my entire family and cousins and their partners and my aunty and her partner up in Noosa as well. Big support around me. I couldn’t do it without them.”
Titmus, in lane three, kept watch on Ledecky in lane four in what became the utimate 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.
Aussie 'over the moon' after realising dream
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 told Channel 7.
"Oh my gosh, I can't believe it. This past year hasn't gone fast or slow but more than anything to get here was a relief.
"To come here and do the job, I'm over the moon."
Titmus and Ledecky both showed their class by embracing after the race and praising the role that each had played in bringing the best out of one another.
"I thanked her, I wouldn't be here without her," Titmus admitted.
"She set this incredible standard, and all credit to her for the swimmer she is. I've just been trying to chase her.
"It's really exciting now that we have this battle going, it's really fun to race. That's the best part about it.
"In the race, I tried to stay as composed as I could and then tried to stick to my race plan. I can't believe I actually pulled it off."
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