Conor McGregor looks to have upped the mind games ahead of his upcoming clash with Dustin Poirier by taunting his rival on social media on Tuesday. The former two-division champion, who takes on the American in their trilogy bout at UFC 264 in Las Vegas on Sunday, uploaded a voice note on Twitter calling Poirier “pea-head”. In the post, McGregor could be heard saying: “Dustin? Pea-head? I'm coming for you pea-head. Silly hillbilly." The pair, who last fought in Abu Dhabi in January, each have a win against the other, although McGregor's did come some time back, in 2014 when the two faced off at featherweight. Sunday’s lightweight encounter, which tops the bill at a sold-out T-Mobile Arena, is viewed as a title eliminator, with the winner expected to be next in line for champion Charles Oliveira. Poirier (27-6) is the lightweight division’s No 1-ranked challenger, while McGregor (22-5) sits at No 5. Poirier’s victory at Etihad Arena at UFC 257, which came via a second-round TKO, represented the first time McGregor had been knocked out in his professional mixed martial arts career. The Irishman, who in the build-up had been extremely cordial with the former interim champion, later promised on social media that it would be “no more Mr Nice Guy”. That appears now to be ringing true, with both McGregor and Poirier exchanging barbs on Twitter last week. In an interview with ESPN, Poirier said his opponent “reeks of insecurity” after McGregor dared him to avoid shooting for takedowns when they meet on Sunday. On Saturday, McGregor responded in an Instagram Live Q&A: “He talks some amount lately. He’s going to pay for that, that’s for sure. That’s not going to be nice.” McGregor had earlier told those tuning in: “[I’m going to] give him a proper head kick. There will be a lot of weapons produced on the night, that’s for sure. He wants mixed martial arts? He’s going to get it. “I’ve been busy putting in the work. Full focus, fully immersed in mixed martial arts. It’s been nothing but mixed martial arts, so I’m ready to put on a show.”