Justin Gaethje Says Conor McGregor's 'On His Knees Begging for a Fight'

Justin Gaethje loves how the tables have turned with Conor McGregor ... telling TMZ Sports it's the Irishman's turn to wait in line for a fight. "I get to pick between Conor and [Khabib Nurmagomedov] right now," Gaethje says. "I can pick whichever…