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Vin Diesel said Conor McGregor withdrew from filming xXx: The Return of Xander Cage following his defeat to Nate Diaz to avenge his loss and reclaim his "manhood."

Per Guilherme Cruz of MMAFighting.com, Diesel told Brazilian TV show Giro Combate: "I had created a role for Conor McGregor, and after he lost to Nate Diaz, he had to go to a dark place, he had to go get his manhood back to fight the second time, so he wasn't able to do this film at the time."

Notorious lost to Diaz at UFC 196 in March this year, making the step up to welterweight. Previously, he had fought at featherweight and unified the division's championship.

The pair fought again in August at UFC 202, with McGregor winning the rematch via majority decision. The 28-year-old followed that up with a knockout win over Eddie Alvarez in November to claim the UFC lightweight championship and become the first UFC fighter to hold two belts simultaneously.

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The Irishman was replaced in the film by fellow UFC star Michael Bisping, as Diesel wanted a character with an English accent.

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A move into acting still seems to be on the cards for McGregor, though—he recently made a cameo in the video game Call of Duty: Infinite Warfare alongside Game of Thrones star Kit Harington, and it appears he may soon appear in HBO's hit fantasy drama, per Fox Sports Live (from 4:30):

McGregor would not be the first UFC star to appear on film—the company's other most popular fighter, Ronda Rousey, has starred in The Expendables 3, Entourage and Furious 7.