Ketlen Vieira v Irene Aldana
STEVE MARCUS / Getty Images

Irena Aldana was set to face off with former women's bantamweight champion Holly Holm in the main event of UFC Fight Night on Saturday, Aug. 1, but the fight has now been postponed after Aldana tested positive for COVID-19. Aldana, who has a 5-1 record since 2018, announced the news on her Instagram after word the fight had been pushed back began to surface earlier on Wednesday. 

"I deeply thank the fans and all the media for their messages of support and the interest shown in the news of the postponement of my fight in 1st, August vs. Holly Holm," Aldana's message read. "We are going through a very complicated world situation and my country is no exception: COVID-19.

"Despite the fact that we have made a camp in total isolation and with the health measures recommended by the authorities, unfortunately I had some symptoms and in the pertinent examinations it was positive. I am still recovering: the first days were complicated in terms of symptoms, but I am much better."

Stepping in for Holm vs. Aldana as the main event at the UFC APEX in Las Vegas will be a middleweight bout between Derek Brunson and Edmen Shahbazyan, which was previously planned to serve as the event's co-headliner. Brunson is riding a two-fight winning streak, taking down both Elias Theodorou and Ian Heinisch in 2019. Shahbazyan is 11-0 in his pro career and 4-0 in the Octagon. He has finished all but one fight in his career, winning nine fights by knockout and one by submission.