Djokovic overcame Roger Federer in an energy-sapping thriller that lasted over three hours in Saturday's semi-finals, and the Serb began to look tired as he dropped serve to a fall behind early in the second set.
In a 47th meeting between the two greats, the stubborn Djokovic simply refused to be beaten as he eked out a fourth successive victory over Federer in a tiebreak decider after three compelling hours.
Karen Khachanov of Russian Federation has reached the final of the Paris Masters after a comfortable straight sets win over Dominic Thiem of Austria on Saturday.
Khachanov will now play his first Masters 1000 final on Sunday against the victor of the blockbuster second semi between Novak Djokovic, who will be back to world number one on Monday, and Roger Federer, who is seeking a 100th career title.
Federer had 17 aces, while Djokovic got five of his eight in his last three service games of the match, raising his level at the right time.
Djokovic told Sky Sports: "It was a spectacular match and one of the best of my career against him".
"It means the world to me", Khachanov said after the match.
"Next to the match I played against (Rafa) Nadal in the Wimbledon semis, this was definitely the most exciting match I've played this year, and probably the best quality match that I was part of".More news: Wayne Rooney returns to England squad for United States of America friendly at Wembley
Sometimes I give him the training rhythm, sometimes it's him.' Asked on what Federer can improve, Luthi said: 'There are always technical innovations, even for Roger who has a fuori dal comune shots. "It's intense, it's good tennis, we care about winning, we don't like losing". You can feel it.
Going into the event, Khachanov had won just three of 19 encounters against players in the top 10 but claimed a fourth such scalp in a week after snapping Djokovic's 22-match winning run.
The 14-time Grand Slam victor will replace long-time rival Rafael Nadal at the top of the rankings on Monday, capping an astonishing revival that began with a fourth Wimbledon title in July.
Earlier, Khachanov showed why he is one of the finest young talents in tennis with a thunderous victory over Thiem.
The 22-year-old Khachanov, ranked 18th, is the first Russian to win here since Nikolay Davydekno in 2006.
Switzerland´s Roger Federer reacts during his semi final match against Serbia´s Novak Djokovic.
Khachanov, a strapping 1.98-metre huge hitter with surprisingly fleet movement around the court for such a big man, took advantage of Djokovic being a little under the weather after a week struggling with flu-like symptoms. But already an established player, a top player.