Former lightweight champion Rafael dos Anjos announced Thursday that he's out of his UFC 254 bout against Islam Makhachev on Oct. 24 after testing positive for COVID-19.

"COVID-19 caught me big time and the doctors cut me out," Dos Anjos wrote on Twitter. "But soon I will be back victorious inside the Octagon."

Dos Anjos versus Makhachev was scheduled to take place on the pay-per-view main card in Abu Dhabi, United Arab Emirates.

It's unclear if the promotion will seek a new opponent to face Makhachev on short notice.

Dos Anjos was looking to snap a two-fight skid, which includes a January loss to Michael Chiesa at UFC Raleigh. The Brazilian, who held the 155-pound belt from 2015-16, is 1-4 in his past five outings.

He was scheduled to compete in the lightweight division for the first time since 2016. His past eight bouts took place at welterweight.

Makhachev, a top prospect in the 155-pound weight class, is riding a six-fight winning streak.