Dave Portnoy says the scheduled fight between Patrick Mahomes Sr. and John Rocker is now off ... and he's alleging Brittany Mahomes' meddling is a big reason why.
The Barstool Sports honcho broke the news of the celeb boxing match's cancelation during an appearance on "The Unnamed Show" Friday ... explaining Brittany and Patrick Mahomes II's agent torpedoed the whole deal.
BLAME BRITTANY The Unnamed Show / Barstool Sports
According to Portnoy, just a few days after his "Rough N Rowdy" promotion announced the Mahomes vs.