Former UFC two-division champion Conor McGregor claims he's retiring from MMA.

Out of nowhere early Tuesday morning, McGregor (21-4 MMA, 9-2 UFC) posted a message on his Twitter account announcing that he's done with "the sport formally known as mixed martial art" and wished his fellow fighters good luck in their future endeavors.

McGregor wrote: "Hey guys quick announcement, I've decided to retire from the sport formally known as 'Mixed Martial Art' today. I wish all my old colleagues well going forward in competition. I now join my former partners on this venture, already in retirement. Proper Pina Coladas on me fellas!"

Just hours after an interview aired on "The Tonight Show" with Jimmy Fallon in which McGregor claimed he was currently negotiating with the UFC about a July return to the octagon, "The Notorious" posted the message on social media. Whether it's a true retirement or just a leverage tactic remains to be seen. A UFC official found the tweet to be "strange" in a text message to MMA Junkie.

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