Shannon 'The Cannon' Briggs will fight Fres Oquendo for the vacant WBA 'regular' title on June 3.
The two-time heavyweight champion confirmed the fight - likely to be held in Hard Rock Hollywood in Florida - on his social media accounts on Thursday and insisted Oquendo "must fall".
Briggs, 45, said ahead of the David Haye-Tony Bellew bout last month that he was "looking forward to making history".
"A three-time world heavyweight champion in three different decades - and I'll be the oldest heavyweight to win a world title as well. I can't wait," he said.
Briggs was on the undercard for Haye's previous fight before the Bellew loss, beating Emilio Zarate at The O2 in May 2016, and was expecting to face Haye next.
Despite Briggs continuing to pursue Haye, a fight never materialised and the WBA ordered Briggs and Oquendo to arrange a fight after plans for a fight with Lucas Browne broke down.