Michael Jordan is coming clean about his epic flu game performance in the 1997 NBA Finals ... saying he didn't actually have the flu -- it was some bad pizza.
Remember, #23 was dealing with "flu-like symptoms" before a crucial Game 5 against the Utah Jazz ... and fought through the pain for a 38-point performance to give the Bulls a 3-2 lead.
But, MJ's trainer, Tim Grover, revealed it was actually food poisoning -- not the flu -- that had Jordan under the weather ... after a late-night order from the only place that was open -- a pizza shop.
When the pie was delivered, Grover says 5 dudes pulled up to Jordan's hotel room ... and the trainer hinted there could have been something fishy going on, saying, "I’ve got a bad feeling about this."
Glover's instincts were right ... 'cause MJ woke up at 2 AM "throwing up left and right."
"So, it really wasn’t the flu game. It was food poisoning," MJ admitted on ESPN's "The Last Dance."
MJ's mom thought it was best he didn't play ... but as we all know, he didn't listen and went on to put up one of the most iconic performances of his career.
Of course, the Bulls won the title over the Jazz in 6 games ... and we take it they didn't celebrate with pizza.