Jermell Charlo Putting $25k On Errol Spence To Beat Terence Crawford

Boxing star Jermell Charlo is REALLY confident his guy Errol Spence Jr. will handle business and remain undefeated on Saturday ... telling TMZ Sports he's putting a $25,000 bet on The Big Fish to beat Terence Crawford.

After years of back and forth, Spence and Crawford are FINALLY slated to throw hands in the ring at T-Mobile Arena in Las Vegas on Saturday ... and it's clear Charlo -- who trains at the same gym as Errol -- has no doubt in his mind who will have their hand raised at the end of the epic matchup.

In fact, we asked Jermell if he's trying to make some money off the fight in case he's right ... and he told us, "Absolutely!!"

"A solid $25,000. That's my guy, I really don't like to go too crazy on betting and stuff, but $25,000 and have fun, you know what I'm saying? Enjoy my night in Vegas and get back home to my family and kids and keep training. I'm on my grind."

We also spoke with former boxer Shawn Porter -- who fought both Bud AND Errol during his career ... and he weighed in on what he's calling "The Super Bowl of Boxing."

"Errol has magnificent technique and Terence is extremely precise -- you're talking about elite versus elite," he told us in Vegas. "Whichever one get there first."