Jake Paul's fight against Nate Diaz was on the same level as one of the most popular fights in combat sports history -- so says former boxing champ Shawn Porter, who tells TMZ Sports Saturday's event felt "just as big as" Floyd Mayweather vs. Conor McGregor!
Porter -- who was on the mic in Dallas for the big matchup -- said the vibes were off the charts throughout the Jake vs. Nate fight ... calling the experience Super Bowl-esque.