Dana White unsure if Conor McGregor vs. Nate Diaz rematch 'will ever happen'

UFC 196 is, by some estimates, the most successful pay-per-view event in the company's history. Attempts at a rematch have been made, but none have been successful. That, said UFC President Dana White on Thursday's SportsCenter, gives him concern there may never be a rematch, despite effort on his part to make it happen.
"We're working on what's next for [McGregor]," White told SportsCenter host Cari Champion. "We're trying to set up a fight right now. It's been a little challenging. Obviou