Conor McGregor faces Rafael Dos Anjos for the lightweight championship on March 5, but the war of words is already well underway.
The Brazilian got his first taste of a McGregor press conference where the Irishman bemoaned the posters for the fight, consistently interrupted Dos Anjos when he attempted to answer questions and gave his prediction for the fight.
Speaking to the Daily Mail, Dos Anjos took aim at McGregor and branded his opponent "classless".
"The guy thinks just because he is dressed nice and drives nice cars that he has class, but he's classless, he's a low-life," Dos Anjos told reporters.
"I knew he was going to talk over me and take my place, that's his style. But I'm going to talk louder on 5 March.
"I knew he was going to try to use all his weapons to make me get mad but I kept calm. He has no respect, he doesn't know the word, it doesn't exist for him.
"He's going to get worse, he's going to do everything to promote himself, do everything for money."
Rafael dos Anjos, right, delivers a kick to Anthony Pettis during a men's lightweight title bout last March. Image: Brandon Wade / AP/Press Association Images.
McGregor accused Dos Anjos of being a traitor for not training in his native Brazil, to which he responded:
"In Brazil, millions of Brazilians leave and a lot of Irish leave Ireland," said Dos Anjos. "These people don't deserve to be called traitors.
"I think he's calling his own people traitors and I want to call all the Irish who live in the USA to be on my side because he called them traitors. I want their support on 5 March."
McGregor is aiming to replicate his Cage Warriors feat of holding two titles at once and in doing so would be the first man in the UFC to hold two title in two different weight classes simultaneously.
"He's making a big mistake," said the Brazilian. "He thinks just because he won two divisions in a small show in Ireland he will do the same thing in the UFC.
"No disrespect, but the UFC is the biggest competition in the world, it's not easy to win two belts. I fought better guys, I fought bigger guys, smaller guys and faster guys before.
"I think Conor is just one more guy that I'm going to put my hands on and I'm going to be victorious for sure."
Download the brand new OffTheBall App in the Play Store & App Store right now! We've got you covered!
Subscribe to OffTheBall's YouTube channel for more videos, like us on Facebook or follow us on Twitter for the latest sporting news and content.
