'Shark Tank' Star Praises A-Rod for Not Blowing Fortune Like Most Athletes

Alex Rodriguez ain't no dumb jock -- he's a legit business mogul who should be a ROLE MODEL for pro athletes who wanna STAY rich after their playing days are over ... so says Kevin O'Leary.

The "Shark Tank" star says he was REALLY impressed with A-Rod when he appeared on the show last season ... saying, "The guy is, for an ex-athlete, very savvy on business."

In fact, Mr. Wonderful heaped all sorts of praise on the guy for figuring out how to invest and run a company while he was still playing ball ... so the transition was easy.

"He's kind of a model of what should happen to athletes," O'Leary says ... "Learn something while you're in the game, you've got your cash to reinvest it."