After coming up short in a spirited effort against Floyd Mayweather Jr. in August, the biggest story in MMA has been the impending return of the biggest star in the sport, UFC lightweight champion Conor McGregor, and who he will fight for his first title defense. A trilogy fight with Nate Diaz was the most widely speculated fight for McGregor, but after Tony Ferguson won the interim lightweight title in thrilling fight against Kevin Lee at UFC 216, suddenly the picture became a little murkier. McGregor himself even added fuel to the fire, posting to Twitter to call out the new UFC champion.