Howard Stern is unloading on Novak Djokovic over his COVID-19 vaccine drama ... calling the tennis superstar a "d****bag," "f***ing a**hole," and a "f***nut" in a fiery rant.
34-year-old Djokovic has been fighting like hell to compete in the Australian Open this month despite the country's strict COVID-19 mandates -- he initially had his visa canceled after authorities claimed he did not meet requirements for a vaccine exemption ... before that decision was overturned on Monday.
Stern -- who's gone after sports stars like Kyrie Irving and Aaron Rodgers for their vax stances in the past -- sounded off on the Joker during Monday's episode of "The Howard Stern Show" ... saying Novak should be kicked out of the sport.
"The first I heard of this guy is he doesn't want to get the vaccine, he's running around ... they should throw him right the f*** out of tennis," Stern said.
"He's a d****bag."
But, what really set Howard off is Novak's claim that getting the jab is a private decision ... saying if that's the case, he shouldn't be out in the public and putting everyone else's health at risk.
Howard's co-host, Robin, points out Novak's view on the situation -- his people have claimed since he recently had COVID-19, he doesn't have to get vaccinated, but Stern says Novak can't be trusted.
"Well that's like saying smoking is a private decision," he added. "Well, that's true, but don't smoke in my face, f***nut. What a dummy. Just a big, dumb tennis player."
Djokovic -- the reigning AO champ -- is currently preparing to compete in the tournament next week ... although it's still unclear whether he'll actually be able to take the court ... as government officials could still boot him from the country.
As for his visa application, Novak claims his agent filled it out and made a mistake when claiming he did not travel prior to arriving in Australia. He also admits doing an interview and photoshoot while positive with the virus last month.