Dustin Poirier had to pull out of his scheduled lightweight bout with Nate Diaz at UFC 230 because of an undisclosed injury, sources told ESPN.
It is not known if the UFC will seek a different opponent for Diaz on the Nov. 3 card at New York's Madison Square Garden.
A heavyweight bout between champion Daniel Cormier and Derrick Lewis was announced as the main event for that card earlier Tuesday.
The fight with Poirier was to have been Diaz's first since August 2016, when he lost a majority decision to Conor McGregor. Diaz (19-11) is considered one of the top stars in the sport.
Poirier (24-5, 1 NC) has won his past three fights. He most recently defeated Eddie Alvarez by second-round TKO on Saturday at UFC Fight Night in Calgary.