Jorge Masvidal will bid for his first UFC world title after stepping in at six days' notice to face Kamaru Usman on Fight Island in Abu Dhabi.
Welterweight champion Usman was slated to face Gilbert Burns at UFC 251 but the Brazilian withdrew.
But UFC confirmed Masvidal, 35, will compete as long as both fighters pass a succession of tests for coronavirus.
Saturday's event is being held on Yas Island in order to minimise any risk of spreading the virus.
Both Masvidal and Usman will need to pass tests for the virus before departing the US, upon arrival in Abu Dhabi and after Friday's scheduled weigh-in.
Nigerian-American Usman won the welterweight title from Tyron Woodley in March 2019 and defended it against Colby Covington in December.
The 33-year-old has only one defeat - which was in 2013 - on his 17-fight mixed martial arts record.
Masvidal has become one of UFC's most popular names and scored a notable win over Nate Diaz in November.
In July of 2019, Masvidal secured the quickest knockout in UFC history when he stopped Ben Askren with a flying knee after just five seconds at UFC 239.