The Fight Island era of UFC events is off to a rocky start as Gilbert Burns has tested positive for COVID-19 and is out of his planned UFC 251 main event with Kamaru Usman, UFC Hall of Famer and CBS Sports HQ analyst Rashad Evans has confirmed. The news comes just one week before the fighters were set to square off in a main event clash for Usman's UFC welterweight championship. 

According to ESPN, the featherweight championship rematch between champion Alexander Volkanovski and former titleholder Max Holloway, originally scheduled as the co-headliner, will serve as the new main event of UFC 251 on Saturday, July 11. 

Burns had become something of a poster-boy for the UFC's COVID era, emerging victorious in bouts against Demian Maia and former welterweight champion Tyron Woodley to earn his shot at Usman and the welterweight title at UFC 251. The pair are longtime teammates, but when financial negotiations broke down between the UFC and Jorge Masvidal, Burns got the call for a third fight in a five-month stretch.

After a training camp in Florida, Burns and his camp flew to Las Vegas, one of four "hub cities" from which fighters will fly to Abu Dhabi for the four events on what the UFC has dubbed "Fight Island." Upon arrival in Las Vegas, Burns, his brother Herbert and one of his coaches reportedly tested positive for the virus.

Upon Burns being pulled from the event, Usman also did not board his flight to Abu Dhabi with uncertainty swirling over whether the fight will be rescheduled or if the UFC would manage to pull a replacement opponent to challenge for the welterweight championship. 

At the moment, with little time to spare, rescheduling may be an option on the table with two big names offering up their services. Jorge Masvidal's manager revealed to ESPN's Ariel Helwani that the reigning "BMF" champion is willing to accept the shot against Usman for the welterweight title on a week's notice. Meanwhile, former interim welterweight champ Colby Covington, who lost to Usman in a main-event classic at UFC 245 last December, said that he's willing to head to Abu Dhabi next week for either a rematch with Usman or a long-awaited grudge bout with Masvidal.