The bad blood is in full flow ahead of Dillian Whyte's face-off against Lucas Browne on March 24.
The two fighters will meet at the 02 in London for their WBC 'silver' title fight, with Browne looking to maintain his unbeaten record of 25-0.
The Australian has been pretty disparaging in his assessments of Whyte.
In fact, it wasn't too long ago that he described him as the "new Chisora", which certainly wasn't intended as a compliment.
"He's very good, don't get me wrong, Chisora also got to a world title shot, but didn't win it, and I think he's much the same," Browne said, quoted via Sky Sports.
"He's in that boat, much of a gatekeeper so to speak for the world title."
It may have come as a surprise then, when Dereck Chisora posted a photo of himself sparring with Browne on Monday, making sure to tag in Whyte:
Whyte and Chisora have a bitter history, of course, and fought each other in December 2016, with the former coming out on top. Any hope of a rematch was dashed when the 29-year-old hit out at Chisora for his lack of ambition following a defeat to Agit Kabayel.
So, to Whyte vs Browne. Chisora has been helping 'Big Daddy' prepare for his old rival and he must have known that it wouldn't go down well.
Unsurprisingly, it didn't take Whyte too long to respond and he hit back with a message:
Perhaps he's asking for trouble there - his win over Chisora was more than a little contentious and one judge actually had the veteran down as the winner.
A good deal of boxing fans felt, at the time, that it was unjust.
Will Chisora point that out? We'll have to wait and see.
Do you think Whyte will beat Browne? Have your say in the comments.
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