Teofimo Lopez vowed to stop Shakur Stevenson in his bid to dethrone him as world champion, adding that his rival would be made to "jiggle my balls".
The WBO super lightweight title holder will defend his crown at The Ring 6 on January 31, against an opponent seeking four-weight champion status.
Stevenson enters as the betting favourite for a local contest between rivals from either side of the Hudson River, set to be held at Madison Square Garden.
But at a Wednesday press conference where Lopez mostly let his father Teo Sr. bandy words with his opponent, he did have one shock-tactic promise.
"I'm going to have Shakur jiggle my balls," he proclaimed to reporters, prompting shocked laughter. "You not excited for this? I'm happy, grateful, blessed.
"This is two of the guys that they say are the best of the best, about to lace it up in Madison Square Garden. We're here to face the best, forget the rest.
"Make sure you keep the odds high on him. I've got a lot of people who are starving and they need to make their money. This is what boxing needs."
Lopez was previously set to fight Devin Haney earlier this year, before negotiations collapsed, but the star feels this latest bout is a far greater prospect.
"When they presented the fight with Devin, he had no motion," he added. "Shakur has motion. This is what boxing needs. We're here to take over.
"We've got a lightweight coming up to try and dethrone [me] I've got to get through him first. When it's all said and done, my hand will be raised once again."
When Teofimo Lopez is in town, you can be sure of a good soundbite or two - though more often than not, they come from his father's braggadocio.
At Madison Square Garden though, his line about Shakur Stevenson's anatomy sparked delighted ripples of laughter and a bemused reply from his rival.
If the mind games start here, then it is hard to say whether they are successful, especially with Lopez Sr. and his inability to cede the media spotlight.
But his son, who spent the first half of Wednesday's press conference scribbling in a notebook, is otherwise keeping his cards close to his chest so far.
He arrives as the betting outsider, but it is not like he was handed his world title out of a Christmas cracker either. Will his secrecy hold the key to success?
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