Ex-WWE star "The Coach" says his money's on Vince McMahon bringing back the XFL ... but thinks the pro wrestling mogul might have another huge plan for his fortune ...

BUYING THE CAROLINA PANTHERS!!

Coach ain't kidding ... telling TMZ Sports that Vince -- whose secret home base is North Carolina -- has what it takes to plop down a serious bid.

"He’s a billionaire, he could come up with the funds, and he’s also at the age where other owners would respect that," Coach said.