The UFC superstar competed in an exhibition match late Friday night at his OG gym in Crumlin, Ireland. Sure, Conor's wearing headgear so already you know it's basically a sparring sesh. But, he looked great and, in typical Conor fashion, he showboated throughout the match.

Check out the video ... Conor squares off against amateur Michael McGrane, reportedly an electrician who competes in Dublin. The Irishmen put on a show for the packed crowd with a four-round bout.

McGrane was no match for Conor, obviously ... as the superstar smothered his opponent with jabs while deftly switching stances -- from Orthodox to Southpaw -- throughout the match. He did a great job cutting the ring too.

The match was reportedly a secret ... cause McGrane was listed on the "Good Friday Show" card but his opponent was marked as "A. Another." After the fight ... McGregor mugged for the cameras with fans while showing off his Proper 12 whiskey.

The event helped raise money for the boxing club ... with the money going to help young fighters cover their travel expenses as they set out to compete throughout the year.