The replacement was officially announced by representatives of the organization.
The bout of American middleweights will be a rematch – in December 2021 Curtis inflicted the last defeat on Allen, knocking him out in the second round.
Brendan Allen has since reeled off six straight wins, finishing Paul Craig with a third-round rear-naked choke in his last fight, and has climbed to No. 6 in the UFC’s middleweight rankings.
Chris Curtis, on the other hand, has had mixed success in his subsequent appearances, but put his career back on track with a split decision win over Marc-Andre Barrio in January of this year.