After Floyd Mayweather stopped Conor McGregor via 10th-round TKO last August, the two combatants exchanged pleasantries at the post-fight news conference that made it seem like all of the animosity between the two heading into the fight was a ruse.

However, the rivalry may not be over.

Mayweather took aim at the UFC lightweight champion on Twitter by referencing McGregor’s run-in with an Irish cartel that took place on late 2017.

“I already [expletive] you up in 2017 now they about to [expletive] you up in 2018. You’re about to start your new year off with a bang,” Mayweather tweeted.

Back in November, a report surfaced that McGregor allegedly punched a mafia associate believed to be in his 50s at a pub in Ireland following an argument. A separate report from The International Business Times claimed that those actions caused a €900,000 price to be put on McGregor’s head and that the Irishman pay protection or risk being harmed. Since then, nothing has come of the situation but Mayweather decided to take a shot at McGregor with that story.

It didn’t take long for McGregor to respond. And his return tweet was simple.

“I am the cartel.”

McGregor has stated that he wants another crack at Mayweather in a boxing right. Dana White has said that he expects his lightweight champion to defend his title sometime in 2018. Perhaps this exchange was done to drum up interest in a rematch.

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