McGregor will take on the American for the third time at the T-Mobile Arena in Paradise, Nevada, this weekend with both men having scored a win over the other.
Following a friendly build-up to their bout earlier this year, the Irishman brought a lot more hostility to the press conference, kicking out Poirier during the face-offs.
McGregor, 22-5, beat Poirier by TKO at UFC 178 in 2014 but lost his most recent bout to the same opponent by the same method at UFC 257.