PARIS -- Qualifier Filip Krajinovic reached the Paris Masters final after an upset 6-4, 6-7 (2), 7-6 (5) win against ninth-seeded John Isner on Saturday.
The 25-year-old Serb slid onto his back and sobbed, his arms raised, after sealing victory on his first match point. Krajinovic then knelt and kissed the court.
"The emotions are amazing, big. When I served for the match my hand was shaking," Krajinovic said. "It was tough to control the emotions. Best day in my life but the tournament is not over yet."
He will play for his first career title against 16th-seeded American Jack Sock, who comfortably beat home favorite Julien Benneteau 7-5, 6-2. Sock has never won a Masters title and can qualify for the season-ending ATP Finals London if he does so here.
Sock dropped his serve twice but broke the 35-year-old Benneteau's serve five times. The 25-year-old American will go for his third title of the year and fourth of his career.
"I was able to ... play my game, swing big," Sock said. "I'm going to have to bring my A-game tomorrow. ... Everyone knows (Krajinovic) is a very talented player and he's showcasing that."
For big-serving Isner, the defeat ended his bid to reach London.
"Very disappointing. I had an opportunity here to do some things I've never done before," said Isner, who was also hoping to break into the Top 10.
Isner was a runner-up in Paris last year and again fell short of an elusive first Masters title.
"I have been very close in tournaments, especially Masters events. I just haven't broken through," he said. "This one is going to sting because I knew I was the highest-ranked player in the semifinals."
Krajinovic is the lowest-ranked player in a Masters final since 191st-ranked Andrei Pavel in Paris in 2003.
The 77th-ranked Krajinovic had only won 17 matches in his whole career -- thwarted by a wrist injury -- before this tournament.
Krajinovic, who looked fresher on court than Isner, is the first qualifier to reach a Masters final since Jerzy Janowicz in 2012, also in Paris.
Krajinovic was helped by not having to play his quarterfinal because top-ranked Rafael Nadal pulled out with a right knee injury. Nadal has not said whether he will be fit enough to play in the season-ending ATP Finals, starting Nov. 12 in London.
Serving for the first set, Krajinovic held to love when Isner sent a two-handed backhand into the net.
With Isner serving at 4-4 and 40-30 in the ninth game of the second set, the match was halted for six minutes while medical staff attended to a female spectator, who was taken away. She appeared fully conscious and had her eyes open.
Isner dominated the second-set tiebreaker and clenched his fist after leveling the match with an ace.
The 32-year-old Isner couldn't take advantage after forcing a break point at the start of the third set, and Krajinovic saved another crucial break point in the ninth game.
"I actually went after it and I missed the ball by a few inches," Isner said. "With how well I was serving today, that was essentially a match point."
In a tense decisive tiebreaker, Isner led 3-0 but Krajinovic rallied to move 5-4 ahead. Isner's 31st ace steadied him but a superb return to Isner's feet on the next point gave Krajinovic match point on his serve.
"When I was up 3-0 I was actually feeling very good," Isner said. "But he hit two unreturnable serves."