Conor McGregor over a promised $500,000 donation. McGregor vowed to donate the sum to his rival's foundation just days before their January rematch in Abu Dhabi.
But after being stopped in the second round, McGregor failed to follow through with his side of the deal and Poirier took to social media to call him out.
McGregor responded in a fit of rage, accusing his fellow lightweight contender of failing to explain where the money would be used.
He also claimed their recently-agreed trilogy fight was now off and that Poirier should seek a new opponent. Eventually McGregor donated the same sum to a different charity in Poirier's home state of Louisiana - and the American now considers the matter put to bed.
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