Cris "Cyborg" Justino will defend her women's featherweight championship against Holly Holm in the main event of UFC 219 in Las Vegas on Dec. 30, the company announced Thursday.

Cyborg (18-1), who won the vacant title by defeating Tonya Evinger on July 29, will be making her first defense. Holm (11-3) is a former UFC women's bantamweight champion who lost three straight fights before defeating Bethe Correia via knockout on June 17.

This fight will be Holm's second at featherweight after she competed for the inaugural featherweight championship but fell to Germaine de Randamie in a unanimous decision at UFC 208 in February 2017. De Randamie later vacated the title after she refused to defend it against Cyborg.

The two mixed martial artists had been feuding on Twitter recently, seemingly laying the groundwork for this fight. 

CBS Sports will update this story shortly.