He, of course, beat Chad Mendes last month in Las Vegas in a nail-biting fight that had millions glued to their screens.
Next up for Conor McGregor is Jose Aldo – in the city's MGM Grand Garden Arena, in December.
And while the Dubliner has a packed training schedule, he's also enjoying a little down time in Sin City, making club appearances that delight his many fans.
Last night, however, was strictly about kicking-back and having fun: he was spotted in Vegas's famed 1 OAK venue, a favourite of celebrities and sports stars.
The club took to Instagram this evening to share news and a snap of Conor: "UFC champ Conor McGregor ended up at 1 OAK last night," it said in an accompanying caption.
It is not known whether his long-term girlfriend, Walkinstown-native Dee Devlin, 28, accompanied the 27-year-old.
Among those to regularly frequent the Las Vegas Boulevard venue are Kim Kardashian, Ciara, Chris Brown, Pitbull, and Katy Perry.
Scott Disick is furthermore a big fan; he's also paid five-figure fees to hang-out at there. Though most recently, he was forced to cancel a much-hyped appearance shortly after his July breakup with Kourtney Kardashian.
Conor also does club appearances in the city: following his win against Mr Mendes, he was signed up to do a pool-party at the SLS Las Vegas Hotel & Casino.
However, Crumlin-boy Conor, who spent time on the dole queue before he found fame, says he'll never "forget the struggles".
"I never forget where I came from. I never ever forget the hard times,” he has explained.
“I pinch myself because I am surrounded by luxury. But make no mistake – it’s luxury built on sacrifice.”
He and Dee often celebrate his milestone wins with OTT Las Vegas shopping sprees, and he also recently splashed out on matching his 'n' hers Audemars Piguet diamond-encrusted watches, each costing between €30,000 to €50,000, for him and his girlfriend.
Speaking to the Guardian after his win over Chad Mendes, he admitted: “We went shopping for ten hours straight yesterday.
"I got us a limo and we stuffed it with shopping bags so it was a great day and then we had a great night."