UFC 257 Results: Dustin Poirier Knocks Out Conor McGregor ABU DHABI, UNITED ARAB EMIRATES - JANUARY 23: (R-L) Dustin Poirier punches Conor McGregor of Ireland in a lightweight fight during the UFC 257 event inside Etihad Arena on UFC Fight Island on January 23, 2021 in Abu Dhabi, United Arab Emirates. (Photo by Jeff Bottari/Zuffa LLC) Dustin Poirer got his revenge in the UFC 257 main-event, knocking out Conor McGregor in the second round. The six years that had passed between Conor McGregor and Dustin Poirier’s first meeting, a featherweight affair back in 2014, were crucial as the duo entered their rematch. The biggest question to be answered on Saturday in Abu Dhabi was really who had grown more.