“Katie was so far in front of us that when I started to coach her,we couldn’t even have that conversation. Arnie was a 4:12 swimmer and at that stage Katie went 3:56. That’s a 16-second difference,” Boxall said. “We started to believe and just started chipping away. Katie was an outlier.”

Boxall and Titmus have developed a coaching chemistry that has now propelled the swimmer into the history books. They don’t always see eye-to-eye but they are extremely close and Boxall has found the secret to unlocking the potential of the powerhouse freestyler.

“I think I went outside my body. I just lost it. That’s a moment of being with this girl for five years and having a dream together.”

Dean Boxall on his exuberant celebration

After the race,Titmus said she simply could not have beaten Katie Ledecky without him.

“He’s sacrificed a lot of his family life from his kids. He puts 100 per cent into being a swimming coach and I would not be here without him,” Titmus said.

Boxall was born in South Africa and moved to Australia with his family when he was seven. He spent a life in and around the pool but was hardly an instant success as a coach. It was the support of a coaching great,Michael Bohl,and former Australian head coach Jacco Verhaeren that finally helped Boxall establish himself on the elite and international scene.

“I never quite fit the mould,” Boxall toldThe Sydney Morning Heraldin a 2019 profile. “That’s why I will always be grateful to Jacco,because I don’t fit the mould. I never have.

“Bohly seemed to think I did and he believed in me. But not the hierarchy above. There were some tough guys up ahead and they didn’t think my personality would have suited. People were always worried I’d burn out. But I’ve had energy since the moment I was born.”

Boxall is also in charge of other Australian swimmers including Mitch Larkin and speedy freestyle pair Mollie O’Callaghan and Meg Harris.

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