The legendary Serbian, 16 years Alcaraz's senior, recovered from a set down to triumph 4-6 6-4 6-3 6-4 in an epic three-hour and 37-minute showdown on Rod Laver Arena.
After having his serve broken late in the first set to go down 4-5, Djokovic took a medical time-out to have his left thigh strapped.
The 37-year-old might have lost the first set after returning to the court, but the break allowed him to refocus for his charge at Alcaraz for the rest of the match.
STOP IT, YOU TWO 🤯— #AusOpen (@AustralianOpen) Tennis from another planet between Novak Djokovic and Carlos Alcaraz! �@wwos • @espn • @eurosport • @wowowtennis • #AusOpen • #AO2025 pic.twitter.com/mZ2TcJBEGlJanuary 21, 2025
After securing the victory just before 1am on Wednesday morning, the former world No.1 hugged coach Andy Murray.
"I just wish this match today was a final," Djokovic said.
"One of the most epic matches I have played on this court, on any court really.
"If I lost the second set, I don't know if I would continue playing.Â
"I felt better and better and managed to play a great couple of games to end out the second set."
Carlos Alcaraz took the first set but could not match Novak Djokovic subsequently. (Joel Carrett/AAP PHOTOS)
If Djokovic is able to win a record-extending 11th Australian Open title, it would make him the most successful singles player of all-time.
The seventh seed is locked on 24 major titles, the same number as Margaret Court won during her singles career from 1960 to 1973.
Djokovic will face German second seed Alexander Zverev, who is aiming to win his first major title, in the semi-finals on Friday night.
If Djokovic can get past Zverev - which would be his 100th win at the Australian Open - world No.1 Jannik Sinner could be all that stands between him and becoming the undisputed greatest of all-time.
Novak Djokovic's children watched the entirety of his match despite the late 1am finish. (Lukas Coch/AAP PHOTOS)
Djokovic has won his past two encounters against Alcaraz since the world No.3 embarrassed him in straight-sets in last year's Wimbledon final.Â
Alcaraz was attempting to become the youngest player to achieve a career grand slam, having claimed last year's French Open and Wimbledon crowns to go with his US Open title in 2022.
He equalled his best result at Melbourne Park, after also bowing out in the quarter-finals at last year's Australian Open.
It comes just two days after Djokovic boycotted the standard on-court interview following his fourth round win over Jiri Lehecka due to being incensed by an on-air sledge from veteran Channel Nine newsreader Tony Jones.
Even though Djokovic on Monday "acknowledged" Jones' apology, the superstar's entourage still appeared to be unhappy with the host broadcaster after a member of the box threw a sweatband over one of the cameras.
But he did conduct a lengthy, good-natured on-court interview with Jim Courier in which he referenced his watching children, wondering why they were still up at 1am.
"I love you, thank you for supporting me, but when are you going to sleep," he said, to laughter from the crowd.
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