Jake Paul says he ain't just talk when it comes to fighting celebrities -- telling TMZ Sports he'll throw hands with ANY famous person who wants smoke ... as long as they "pull up" to his house.
Of course, Jake's brother, Logan Paul, DID fight a guy who showed up to his L.A. home looking for a scrap recently -- an Ivan Drago wannabe who got the CRAP beat out of him in Logan's backyard.
Now, with celebrities like Justin Bieber calling out Tom Cruise for an MMA fight (even though he later backed down) .