Brett Favre frickin' LOVES Conor McGregor ... and says he's super pumped for the Khabib Nurmagomedov mega-fight.
Oh yeah ... and he told us who's gonna win too.
TMZ Sports recently spoke to Favre -- who just took a family vacay to Ireland -- about his UFC obsession ... particularly the Notorious.
"I like watching the guy fight. Love watching the guy fight. I think he's a hell of a fighter."
Favre says he's pumped for what some -- including Mark Wahlberg -- say is gonna be the biggest MMA fight ever .