Francis Ngannou says Derrick Lewis vs. Ciryl Gane is a great fight ... but what it's not?? A title fight, 'cause there's already an undisputed UFC heavyweight champ -- and it's him.
TMZ Sports talked to 34-year-old Ngannou on Friday ... ahead of tonight's interim heavyweight title fight between Lewis and Gane at UFC 265.
"It's just a contender fight. It's not an interim or whatever them guys are talking about. It's a contender fight. They're fighting for the #1 spot contender. It's not a title fight for me.