For the second straight year, Dominic Thiem will play for the Nitto ATP Finals trophy, with a first-time champion guaranteed to be crowned in London.

In Saturday’s opening semifinal, Thiem survived collapsing against five-time winner Novak Djokovic, 7-5, 6-7 (10), 7-6 (5), to avenge his 2020 Australian Open final defeat to the world No. 1 and clinch his 300th career match win.

"It was for sure a mental battle. I got so tight in the second set tiebreak," Thiem said afterwards on court. "I thought that after my first big title in New York, maybe I'm going to be a little bit more calm. It was a mistake, I guess. I was just as tight and nervous as before. It was so much on the edge, the match."

Djokovic staved off four match points in the second set tiebreaker— two came on Thiem's serve, with the Austrian double faulting in the first instance at 7-6. The Serbian clinched the set when his opponent's backhand found the net.


ATP Finals: Thiem mounts late comeback to edge Djokovic for 300th win

In the third set, neither player was able to create a break point chance, resulting in a decisive tiebreaker. Djokovic built a 4-0 lead, but this time, it was Thiem’s turn to mount a heralded comeback. The Austrian claimed six consecutive points, thanks to go-big-or-go-home hitting and would go on to edge Djokovic for the second year running at the season-ending event in two hours and 54 minutes, holding in all 18 of his service games.

"Well done Dominic. You showed guts when you were down in the third set tiebreak and you deserved the win," Djokovic tweeted following his narrow loss. "It was pleasure competing with you once again. Amazing match."

After losing his first five encounters with the 17-time major champion, Thiem has taken five of their last seven. In Sunday’s title match, the 27-year-old awaits the winner of Rafael Nadal and Daniil Medvedev.