Terence Crawford took to Twitter to troll Amir Khan after the Brit questioned the world champion's resume.
The rivals will clash for Crawford's welterweight world title at Madison Square Garden in New York on April 20.
And Khan questioned the American's record despite him being a three-weight champion.
The Brit said: "I've fought better opponents, beaten better opponents. Okay fine, he's unbeaten, but I'm sure I would be unbeaten if I fought all the guys he did."
Crawford was quick to pick up on the quote and made the point that the pair shared a common opponent in Breidis Prescott.
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And while Crawford outpointed Prescott in 2013, Khan was knocked out after just 54 seconds when they met in Manchester five years earlier.
And the champion posted a video of said knockout in response to Khan's claim.
The challenger later doubled down on his claim, telling Boxing Scene : "I think they’re definitely overvaluing him, obviously, looking at the level of opponents he’s fought.
"Look at the caliber of opponents. I’m on a different level, really, the way I’ve fought different guys and I’ve jumped up weight to fight people and taken big risks and big fights. I don’t think he’s took any risks yet.
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"I feel like they’re going to always doubt me, they’re always going to say I don’t have a chance. But really there’s only a year difference in our ages; he’s 31, I’m 32.
"I’m at the peak of my career now. I feel as strong as I’ve ever been. I feel quicker than ever. They’re gonna always put me down in ways and say he’s a better fighter but we’re not going to know until the fight happens on April 20.
"Obviously people are going with whatever his record says because he’s unbeaten and I’ve had a few losses. People are always gonna stay with the unbeaten fighter. But the level of opponents he’s fought are nowhere near as good as mine."
