Shanghai - Stefanos Tsitsipas said that he scares the "Big Three" after the young Greek stunned world No 1 Novak Djokovic to reach the Shanghai Masters semi-finals on Friday.
The 21-year-old has now defeated Djokovic, Roger Federer and Rafael Nadal this year and faces another major talent on Saturday in the form of 23-year-old Daniil Medvedev.
Tsitsipas recovered from losing the opening three games in just seven minutes to shock the reigning champion 3-6, 7-5, 6-3.
Calling it the best comeback of his nascent career, the seventh-ranked Tsitsipas said he dreamt of beating the "Big Three".
But rather than being intimidated by then, Tsitsipas said: "I honestly feel like they are more threatened than I am and that makes me more relaxed on court.
"I know I just have to hang in there and be able to be more aggressive.
"Once you get aggressive and they see you going for it, I might even say they get scared."
It was a double celebration for Tsitsipas, who also confirmed his place in the prestigious season-ending ATP Finals.
Tsitsipas sealed the deal with a gleeful smash and held both arms aloft. Djokovic met his opponent with a warm embrace at the net.
Djokovic, who had looked imperious up until now, had no complaints.
"He deserved the victory, he was the better player," said the 32-year-old Serbian.
"Second and third set I started off very well, but then I wasn't sharp.
"I lacked that little bit of dynamic movement and acceleration in my shots.
"I didn't have any breakpoints for two sets. I mean, he did serve well, credit to him, but just wasn't pleased with the way I played."
Asked if Tsitsipas has the potential to be number one, Djokovic replied: "He definitely has, yes."
Djokovic says that he is fully recovered from a shoulder injury and did not drop a set in winning the title in Tokyo last week.
He had carried that ominous form into Shanghai and threatened to blow Tsitsipas away in the first set.
"He hit some insane shots, completely unbelievable, which I had no chance of getting back," said the Greek.
"I was saying to myself, how is this even possible?"
But Tsitsipas found his feet in the second set, winning on a tie break, then went 3-1 up in the decider when Djokovic planted a forehand wide on the third break point.
Tsitsipas grabbed his place at the ATP Finals after fourth-ranked Medvedev tamed self-styled "wild horse" Fabio Fognini 6-3, 7-6 (7/4) in their quarter-final.
Fognini was vying for a ticket to the Finals in London.
Medvedev - another of the next generation - sent down 12 aces to help see off Fognini and said: "I don't know what happened, my serve was crushing it."
The Russian has a 12-0 record in quarter-finals this year and Djokovic this week described the US Open finalist as a "very complete" player.
Federer, the 20-time Grand Slam champion, faces young German Alexander Zverev later Friday in his quarter-final.
The other match is between Austria's Dominic Thiem, who beat Tsitsipas to the China Open title on Sunday, and Italy's Matteo Berrettini.
US Open champion Nadal is not in Shanghai because of a wrist injury.