'What you gonna do?': Tim Tszyu cops bizarre 'flat-footed' spray from American rival

Undefeated Aussie boxer Tim Tszyu has vowed to knock out one-time American champion Keith Thurman when the pair clash in Las Vegas next month.

Tszyu (24-0) went face to face with veteran Thurman (30-1) at a press conference for the first time since their bout was confirmed last week.

The pair - who will fight at Tszyu's weight but not for his WBO super welterweight belt on March 31 - sat on opposite tables separated only by legendary presenter Jimmy Lennon Jr on Thursday morning.

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While Tszyu looked a little nervy and was relatively humble ahead of his big-time American venture, 35-year-old Thurman hammed it up for the media and delivered the first verbal blow between the fighters.

"You're fat feet, slow... Australia, that's a small island very far away, and I did not know flat-footed Mexicans were born in Australia, Tszyu," Thurman said to laughter.

"Mexican Tszyu, what you gonna do?"

The Aussie struggled to get a word in edgewise while the American performed his act.

Tszyu did reveal he wants to continue his father Kostya's legacy and take America by storm so their family name could sit atop the boxing world once more.

But that claim only egged on Thurman to ridicule the Aussie further.

"They say you come from Down Under and I am trying to put you under mate," Thurman said.

"I want him to go, tail tucked, head down back to his daddy in Australia.

"Unfortunately the title will not be on the line but his pride will be, and that's good enough for me."

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Tszyu had struggled to land an opponent in America since Jermell Charlo was forced to withdraw from their January 2023 bout due to a broken hand.

The unbeaten Aussie has since beaten Tony Harrison, Brian Mendoza, and Carlos Ocampo in Australia while waiting for his shot in the States.

Lennon said Tszyu "has now made it" in the US, but the fighter denied that was the case.

"I haven't made it, the making begins when I beat Thurman," Tszyu said.

"He's the first name on the list. This is the takeover for me.

"My goal is for our last name to be the greatest boxing family who ever lived. It's big aspirations, but I've called it here and we'll see how far we get."