The mystery man behind Aussie pool queen Ariarne Titmus

Ariarne Titmus has taken Australia and the world by storm with her stunning performances in the pool in Tokyo.

The 20-year-old has established herself as Australia's new queen of the pool, with two gold medals and a bronze to her name.

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Titmus' exploits have captured the hearts and minds of viewers right around the country, with fans keen to learn more about the nation's newest Olympic superstar.

The Tasmanian-born swimmer's coach Dean Boxall grabbed headlines after Titmus' first gold medal in Tokyo, with one of the greatest celebrations you're ever likely to see.

Boxall has been by Titmus' side throughout the Games, riding her every race and passionately cheering on from the stands.

Images of her parents and sister cheering Titmus on from Australia have been beamed around the world, and their pride for the 20-year-old is clear for all to see.

However, there's another man in the swimmer's life who has largely remained anonymous so far at these games: her boyfriend Kyle Niesler.

Titmus has declined to comment on her relationship with Niesler in the past, instead dedicating her focus to an Olympic dream that she's been realising in Tokyo.

The pair have reportedly been dating for more than a year and can be seen in numerous happy snaps together on social media.

Niesler is also an accomplished swimmer but missed out on a ticket to Tokyo after failing to qualify in the men’s 200m individual medley at the Australian swim trials.

The former Griffith University student is also a junior Queensland champion, but his relationship with Titmus has remained somewhat of a mystery for the public.

Titmus has happily shared photos of the pair enjoying the sun together in Noosa but has so far declined to speak publicly about their relationship.

Ariarne Titmus and boyfriend have plenty to celebrate

Among some of the photos of the pair on Instagram, the pair can be seen celebrating Titmus' success at the national championships in April.

One can only assume there will be more celebrating to be had when Niesler welcomes the 20-year-old home from her breakout Olympic Games success in Tokyo.

Titmus still has a final in the 800m freestyle to swim and admits that she's "absolutely buggered" after a gruelling schedule in Tokyo.

Speaking after finishing second in her 800m freestyle heat, Titmus said she had a new-found level of respect for American legend Michael Phelps - who won an astonishing 28 Olympic medals across his career, including eight (six golds and two bronze) at the 2004 Athens Games.

"I knew I wanted to be under the 8:20 mark to be safe," Titmus said.

"It's a big day today. I only had one and a half hours in my hotel room. I'm absolutely buggered. I will swim down quickly and get home.

"This is probably my toughest back-up and... a really deep field. I knew I had to be tough and swim a solid swim to get through...

"Honestly, I'm exhausted. I keep thinking back to Beijing, it was the same as this morning's heats. (Michael) Phelps won eight (medals). I have done two and I'm wrecked. It puts into perspective for me how amazing he was. I'm going to rest up as much as I can and get ready for my last race at the Olympics."

Watch 'Mind Games', the new series from Yahoo Sport Australia exploring the often brutal mental toil elite athletes go through in pursuit of greatness:

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