Wanna see Logan Paul throw fists at his brother, Jake Paul?? Well, better hope for a crappy Thanksgiving in the Paul household.
Logan tells TMZ Sports the ONLY way he'll step in the ring with his YouTube star little brother is if the two have "real-life" beef.
Judging by the way the two palled around when we got them at LAX this week ... don't bet on that happening any time soon.
It's too bad ... 'cause the two have been training like maniacs for their August 25 superfight with KSI and Deji -- so a Paul showdown would be must-see (YouTube) TV afterward.
BUT ... if the brothers WERE to hypothetically ever step in the squared circle -- Jake did give us his thoughts on who he thinks would win ... and maybe that spurs some drama among the Pauls?!