PARIS - Russian underdog Karen Khachanov ended a dramatic week with his first ATP 1000 title after stunning the to-be world No 1 Novak Djokovic 7-5, 6-4 in the 2018 Paris Masters final here on Sunday.

The unseeded Russian triumphed his first ATP 1000 final over the four-time winner in one hour and 38 minutes.

"It's one of my biggest titles so far, biggest achievement. In general, it's a breakthrough season. And this title, it's a good year-end," Khachanov told a news conference.

Khachanov was riding on a wonderful trip in the French capital this week, as he registered three victories in a row against world Top 10 players, John Isner, Alexander Zverev and Dominic Thiem, en route to Sunday's final.

Djokovic broke for the first time for a 3-1 lead in the first set, only to see his Russian rival's quick response in the very next game. Khachanov continued to press on for his second break in the 11th game and served out the opening set at 7-5.

The third break arrived for Khachanov in the third game of the second set. He built a 4-2 advantage later on with an ace, as Djokovic seemingly didn't recover from fatigue following his three-hour semifinal tussle against Roger Federer.

Despite maintaining his next two serves, Djokovic failed to cut the deficit in his opponent's service. His long backhand in the 10th game earned the Russian hopeful a ground-breaking title of career.

"Novak started with a really high intensity. I knew that that's normal the way he's playing from the beginning, like moving you left, right, left, right.

"It's sometimes tough to resist, and maybe I did a couple of mistakes. After a few games, I could increase my level of the game. I started to move him and maybe he didn't expect that I could do it after being down, you know, 3-1 with a break," Khachanov pointed out.

Djokovic saw his 33rd ATP Masters 1000 title which could tie Rafael Nadal's record relinquished, but had already secured his top place at the upcoming ATP Rankings following Nadal's withdrawal from the tournament earlier this week.

Djokovic admitted that he didn't recover well from the semifinals, but paid more tribute to Khachanov's performance.

"I don't want to talk about that (fatigue). I want to talk about how well he played all week and he absolutely deserved to win the match today. All the credit to him," Djokovic said.

The doubles title went to Marcel Granollers and Rajeev Ram, who beat Jean-Julien Rojer and Horia Tecau 6-4, 6-4.

The Paris Masters is the final stop prior to ATP Finals later this month in London. Kei Nishikori has replaced Juan Martin del Potro, hampered by a right knee injury, to join Novak Djokovic, Rafael Nadal, Roger Federer, Alexander Zverev, Kevin Anderson, Marin Cilic and Dominic Thiem at the eight-player event.