Riding on a relentless attack, Australian tennis star Dominic Thiem bounced back in a nail-biting match to beat the Novak Djokovic and become the first player to reach the semifinals of the 2019 ATP World Tour Finals.

Thiem, who had stunned Swiss legend Roger Federer in straight sets last Sunday in his first match in Group Bjorn Borg, came from behind to defeat Djokovic 6-7 (5), 6-3, 7-6 (5) on Tuesday evening.

“This was really one of these special matches, what I’ve practised all my life for, all my childhood for,” Thiem was quoted as saying by the ATP Tour website. “Really epic one in an amazing atmosphere, beating a legend of our game. And also I’ve qualified for the semi-finals, which is the best,” he added.

Meanwhile, the world number 2 said that Thiem deserved to win. “I thought he deserved to win. He just played very courageous tennis and (was) just smacking the ball. He went for broke,” Djokovic said.

“The entire match he played same way he played the last point. I have to put my hat down and congratulate him, because he just played a great match,” he added.

It is to note that the loss keeps Djokovic, 440 points behind number 1 Rafael Nadal in the battle for year-end number 1 in the ATP Rankings. The Serbian is looking to finish year-end No. 1 for the sixth time, which would tie Pete Sampras’ record (1993-98).

Earlier, Federer, after losing to Thiem, defeated Matteo Berrettini from Italy 7-6 (2), 6-3. As the six-time champion lost his first match to Thiem, he has to now defeat Djokovic on Thursday to reach the semifinals.