London: Dominic Thiem made sure this year's ATP Finals didn't begin the same way last year's ended.
Thiem outlasted Stefanos Tsitsipas in a rematch of the 2019 final, beating the defending champion 7-6 (5), 4-6, 6-3 Sunday in the opening singles match of the tournament inside a largely empty O2 Arena.
In the late match, Rafael Nadal had a much easier time against newcomer Andrey Rublev, beating the Russian 6-3, 6-4 in just 1 hour, 17 minutes.
Nadal is looking to cap a season in which he earned his record-equaling 20th Grand Slam title and 1,000th match win on tour by capturing his first trophy at the ATP Finals. He has qualified for the season-ending event for a record 16 straight years but lost in the final twice and missed six editions because of injuries.
It's important to start well, of course, for the confidence, because winning in straight sets helps, Nadal said.
"I played solid with my serve. I didn't suffer much, and that helps to play more relaxed on the returns.
Thiem, who won his first major at this year's U.S. Open, broke Tsitsipas for a 2-0 lead in the third set with a drop shot at the net and converted his second match point when Tsitsipas sent a forehand wide.
Tsitsipas beat Thiem in a third-set tiebreaker in last year's final to clinch the biggest title of his career. But he let the first-set tiebreaker slip away this time, after leading 4-1 and 5-3. Facing set point, the Greek failed to put away a fairly simple overhead at the net before sending a lob long to hand Thiem the lead.
That was the silliest thing that ever happened to me, Tsitsipas said about his overhead shot. I had ball over the net, and I decided to play forehand instead of a smash. I don't know what kind of decision was that.
Tsitsipas broke for a 2-1 lead in the second set with a forehand passing shot before leveling the match. He had a chance to break back at 3-1 in the third but netted a backhand, letting out a scream of frustration after the miss.