Niall Horan had a go at impersonating Conor McGregor as he guest hosted Jimmy Kimmel Live on Tuesday night.
The Mullingar man, 27, interviewed guests on the popular American late-night talk show and proved popular with viewers, who especially enjoyed his McGregor impression.
One person tweeted: "Niall Horan's impression of Conor McGregor is spot on."
Another said: "Lol well we have a clone double ready, Conor move out the way. Send Niall in the octagon haha."
Someone else commented: "IT'S SO GOOD AHHH."
Horan also roasted Americans over Irish stereotypes on Tuesday's show.
Niall noted: "As I said, I'm from Ireland and when people find out I'm Irish, that's all they want to talk about. Everybody seems to be from Ireland in America.
"They're like 'OMG you're Irish?! My Dad's brothers neighbour is Irish too! Do you know him?'. No, I don't. And guess what? I couldn't give two f**ks about him either."
Niall then cleared up a bit of misinformation that the Americans had been told.
"You guys are misinformed about our traditions. First of all, it's not Patty's Day, as in the p-a-t-t-y you put on a burger. On St Patrick's Day in Ireland, you go to Mass and light a candle with your nanny. Speaking of which, my nanny is 91 today!
"Here in America, you just sing U2 songs all day and puke green beer on your Uber driver. Even your sports teams have it wrong! Let's have a look at the Notre Dame Fightin' Irish. Their mascot is a leprechaun, who looks like Abraham Lincoln had sex with a garden gnome.
"If you want Fightin' Irish, Conor McGregor is fightin' Irish. Guess what, he'll pull your heart right through your arse."
The One Direction singer is no stranger to the UFC star having partied with the Dubliner following his 2016 win over Nate Diaz.
Horan attended the former two-weight champion's after party in Las Vegas with Rory McIlroy.
Posting on Instagram after the bout, Horan said: “Never seen anything like that. It was an absolute honour to be there tonight to watch two absolute warriors go toe to toe in battle. So much respect for both of them. Congratulations Conor you've made our small country proud again and Nate what a fighter and gladiator."
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