Alex Caceres will replace BJ Penn and meet Cole Miller next month at UFC 199.
Penn was removed from his planned Octagon return after a potential USADA violation was disclosed by the former UFC champion.
Caceres (11-8) snapped a three-fight losing skid in January with a decision win over Masio Fullen. The former Ultimate Fighter competitor had gone unbeaten in his previous five fights before the skid, winning four of those.
Miller (21-9) is 2-1 with one no-contest over his last four fights. He was stepping in for Dennis Siver as a replacement to meet Penn.
UFC 199 takes place June 4 from The Forum in California. Luke Rockhold defends his middleweight title against Michael Bisping in the main event.
FOXSports.com first reported the change.
