Unified middleweight/junior middleweight champion Claressa Shields is confident that she would batter YouTube superstar Jake Paul and show him what it's like to go up against a real boxer.

"I, Claressa Shields, will whoop Jake Paul's ass! He can come in the ring weighing 180-pounds and I will come weighing 168 and I will beat the sh-t out of him," Shields told TMZ Sports.

Shields recently spoke to TMZ about the recent fight between Paul and NBA veteran Nate Robinson ... and she says they made a "mockery" of the sport because there are actual boxers who should have gotten the chance to fight on the Mike Tyson vs. Roy Jones undercard instead of social media stars and NBA players.

Paul brutally knocked out Robinson in two rounds. Robinson was making his pro debut, while Paul was taking part in his second fight.

The 25-year-old says it's smart for Paul to keep calling out non-pro boxers ... but guarantees that he would get exposed against a real fighter.

"Jake Paul is making his money, he's doing his thing, but stay away from us real fighters," Shields says.

"And anybody out there that say 'Oh, Jake Paul will destroy her because she's a woman', ... I'm the greatest woman! So, no, Jake Paul won't do nothing with me and if he think he can, he can come see me."

Shields says she's not talking sparring, either -- she would take Paul on in a real fight ... and donate her earnings to the water crisis in her hometown of Flint, Michigan.

As for what the boxing world would think of the potential matchup, Shields thinks people would still pick Paul just because he's a man.

"I've been boxing for 14 years, 2 Olympics but they would still give Jake Paul the nod because he's a man. And it's like, you guys don't know nothing," Shields said.