The young German was emotional after he beat the world No 1 in straight sets 6-4 6-3 to stun the tennis world.
Zverev took his opportunity in emphatic fashion - blasting down three consecutive aces then winning the set when another Djokovic forehand flew long.
The 21-year-old German has always been talked of as the leader of a pack of hungry young tyros aiming to unseat the multiple Grand Slam winners who have dominated the sport for well over a decade. "It's the biggest title I've won in my career", said Zverev. "There is a rule that if something like this happens, obviously you replay points".
The tall South African was disappointed with his own showing in Djokovic's 6-2 6-2 victory in the semi-finals of the Nitto ATP Finals. "I think this is a pretty good stat, especially as he's the best returner we have in the game".
Djokovic himself said Zverev's win could have deeper significance for the men's game.
An incident in the tie-breaker of the first semi-final - the eighth point in which the German appeared to be in the receiving end when trailing 3-4 - sparked the fire.More news: India in Australia ready to beat a home team in turmoil
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We have a lot of coaches, and no disrespect to them, but in order to win Grand Slam matches and become number one in the world it is easier to talk to people who have been there and about their own experiences.
Federer said: "He apologised to me at the net".
"Yes, he has won three Masters 1000 titles before, and has beaten Djokovic and Federer before, but to beat Novak and Roger back to back in one of the biggest tournaments in the world tells him, most importantly, but also the world, that he is going to be the next big thing. I'm incredibly happy and incredibly proud of this moment right now", he added.
Djokovic moved effortlessly around the court, and while Anderson has clearly played better matches over the year, it's churlish to castigate him for a sub-standard percentage of first serves, if only because Djokovic was as adept at returning the first serve as he was the second.
"I lost my serve once against him today", Zverev said.
"If someone told me (I would end the year as number one) at that time it was looking quite improbable", he told reporters.
"I want to apologize for the situation in the tiebreak", said Zverev, who was booed by some of the crowd during his on-court interview. "I was very emotional afterwards". But still I have a lot of things to improve.
"Also huge congratulations to the whole Djokovic team".