"I think I'm the only guy in the world who's rooting against Tiger," Portnoy told FOX Business’ Stuart Varney. "I just never liked him, I thought he was kind of a fraud."
Portnoy ripped the 15-time major winners' hypocritical PR reputation throughout his career.
"He's one of the greatest golfers, but he was all goody-two-shoes in the image, and then he's running around with all these blondes everywhere, his wife's crashing him in a car," Portnoy pointed out. "I don't care. I'm no goody-two-shoes. Just be who you are all the time and be consistent."
Woods is attempting to win his 16th major at this year’s Masters Tournament, just 14 months after nearly losing his leg in a car accident.
But Portnoy admitted he’s not a huge golf fan, anyway.
"The thing about golf, if you root for everybody, you're rooting for nobody," Portnoy said. "In sports, you're supposed to root for people and against people. The golf people – they sit, they clap for every good shot."
"Sports are built for villains, heroes to root against people," he continued, but "there's no doubt it's more fun when [Tiger’s] involved."
But still, Portnoy hopes to see Woods’ "wheels fall off" and those rooting for him "crying in your soup."
Portnoy, who also founded sports betting app Barstool Sportsbook, predicted Woods’ odds will go up if the golfer starts the tournament off on the right foot.
"If he makes it in contention over the weekend," Portnoy noted, "it will be one of the biggest sporting events of all time."