Fans have been wondering for years when the next generation would finally arrive and Sinner answered the question emphatically on Friday with a 6-1 6-2 6-7 (6-8) 6-3 dispatch of Djokovic.
The king of Melbourne Park had entered the much-anticipated match with a perfect 10-from-10 record in Australian Open semi-finals.
Djokovic ended it probably wondering where it all went so horribly wrong on a court he'd made his own for a decade and a half.
Novak Djokovic has finally met his match at the Australian Open. (Joel Carrett/AAP PHOTOS)
The 36-year-old had won his past 33 matches at Rod Laver Arena and, despite losing to Sinner twice in the space of a week in November, was still favoured to advance to yet another Open final and record-extending 37th grand slam title decider.
Instead, the world No.1 - who won three of the four majors last year - remains level with Margaret Court with a record-equalling 24 grand slam singles crowns.
He must wait until the French Open in May to try to surpass Court and take sole possession of the tennis benchmark he craves the most.
Sinner will play Russian No.3 seed Daniil Medvedev in the title match on Sunday night, firmly believing it's time to have his own name etched on the Norman Brookes Challenge Cup.
Medvedev came back from two sets down to beat rival Alexander Zverev 5-7 3-6 7-6 (7-4) 7-6 (7-5) 6-3 in the second semi.
"I don't know what to say, really," said Sinner, the world No.4.
"I came here (in late December), I started off in Kooyong with a couple of exhibition matches and tried to come here as prepared as possible.
"The confidence from the end of last year has kept the belief that I can play against the best players in the world.
"I'm really happy that I can play Sunday in my first final. Let's see how it goes.
"I will come here with a smile and try my best."
On the evidence of not only the past fortnight in Melbourne - where the 22-year-old has yet to drop a set - but the past four months, Sinner is very much the man to beat.
Jannik Sinner is through to his first Australian Open final after upsetting Novak Djokovic. (James Ross/AAP PHOTOS)
Thriving under Australian super-coach Darren Cahill, who guided Lleyton Hewitt, Andre Agassi and Simona Halep to world No.1, Sinner has swept all before him since a sapping fourth-round loss to Zverev at the US Open in September.
He has collected titles in Beijing - where he conquered Medvedev and Wimbledon champion Carlos Alcaraz - and Vienna, made the season-ending championship final in Turin and piloted Italy to a drought-breaking Davis Cup triumph.
Sinner's twin victories over Djokovic at the ATP Finals and Davis Cup had placed the tennis world on notice.
But few could have imagined how he'd put Djokovic to the sword on Friday.
So dominant was Sinner that Djokovic was not able to muster a single break-point chance on his opponent for the first time in his illustrious grand slam career.
Sinner bolted out of the blocks, breaking the 10-time champion in the second game of the match, then again in the sixth to race through the opening set in 35 minutes.
It was the first time Djokovic had conceded a set 6-1 at the Open in a decade.
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As the great Serb made error after error, Sinner cracked winners seemingly at will.
There was no let-up in the second as the Italian claimed two more double breaks to leave Djokovic - and his legion of fans - looking shell-shocked.
Djokovic had recovered from two sets down against Sinner in the Wimbledon quarter-finals two years ago and staged another fightback on Friday.
But even after saving a match point in the tense third-set tiebreaker, there was no escaping this time.
Sinner broke Djokovic for a fifth time in the fourth game of the fourth set, then held his nerve, and serve, three more times to snuff out any comeback and seal victory after three hours and 22 minutes with a huge forehand winner.
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