UFC lightweight champion Conor McGregor has not stepped into the octagon since defeating Eddie Alvarez at UFC 205 in 2016 to retain the UFC lightweight championship. Having lost to Floyd Mayweather in his first professional boxing match this year, who will "The Notorious" face as he returns to the octagon to defend his championship belt?

Rumors suggest that the third and possibly final fight between the McGregor and Nate Diaz feud will take place at UFC 219. The camp of Diaz is currently negotiating for a fight with Tyron Woodley at the pay-per-view event, but is demanding a $15 million pay cut from the UFC. Diaz's boxing coach revealed that the promotion is not willing to give in to his demand and said that Diaz could fight McGregor instead.

"The UFC doesn't want to give Nathan the money," Perez said. "You know, 'cause what Woodley's trying to do, he's trying to get his name up there and he wants to fight the best, so he wants to fight Nathan. But UFC doesn't want to pay Nathan, so why fight him? We can fight McGregor."

However, fighting McGregor for a third time in UFC 219 would mean that Diaz will have to cut weight and make it to the lightweight division. The reason for this is that McGregor's current priority is to defend his lightweight title, otherwise the UFC will take the belt away from him.

For Coach John Kavanagh, the only sensible fight for the lightweight champion McGregor would be a unification bout against the current interim lightweight champion Tony Ferguson who has been waiting for a shot at the championship. The UFC scheduled a match between Ferguson and Khabib Nurmagomedov, but the latter pulled out of the match due to the ill-effects of his attempt to cut weight forcing him to be hospitalized. Instead of Nurmagomedov, Ferguson defeated Kevin Lee at UFC 216 to become the interim lightweight champion.

Aside from his return to the UFC, a report from Daily Star suggests that McGregor could make a comeback to the boxing ring to face his controversial sparring partner on the road to his fight with Mayweather, Paulie Malignaggi.