The heavyweight bout was reported by informed sources close to the situation.
On March 9 at UFC 299 in Miami, 35-year-old Robelis Despain recorded his fifth professional victory by finishing Josh Parisyan by technical knockout in the 18th second of the match.
Waldo Cortez-Acosta, 32, is riding a two-fight win streak, having knocked out Lukasz Brzeski and winning a unanimous decision over former UFC champion Andrei Orlovsky. The heavyweight suffered his last defeat last April, losing a three-round unanimous decision to Marcos Rogerio de Lima.