22:23 CET - Defending champion Jannik Sinner has his first points on the board at the ATP Finals! After a really competitive first set, Felix Auger-Aliassime picked up an injury, which was clearly hampering him in the second, and the Italian went on to claim a 7-5, 6-1 victory over his opponent.
A very good start to the tournament for the world number two. Meanwhile, hopefully the injury is nothing serious for the Canadian.
21:41 CET - After a high-quality set of tennis, Jannik Sinner has the lead against Felix Auger-Aliassime, breaking at the very end to take it 7-5.
The Canadian has battled hard and stuck in there, but he's barely making inroads on Sinner's serve. It is a long way back from here.
20:35 CET - We are just minutes away from the moment the home crowd have been waiting for.
Reigning champion and Italian hero Jannik Sinner is set to begin his defence against the in-form Felix Auger-Aliassime. The last match both players played was... against eachother in the Paris Masters final!
Sinner was victorious then, and he will be the big favourite again today.
Follow the contest live with Flashscore!
16:03 CET - Taylor Fritz's ATP Finals campaign is up and running in fine fashion, putting in a supreme performance to claim a comfortable 6-3, 6-4 victory over Lorenzo Musetti.
Last year's runner-up, Fritz, looked in fantastic touch on the indoor courts, but in truth, Musetti clearly had very little energy left after a gruelling few weeks and playing in the Athens final just two days ago.
15:10 CET - Advantage, Taylor Fritz! A powerful set of tennis from the American has seen him overwhelm home favourite Lorenzo Musetti, capturing the opener 6-3. Has the Italian got a response?
13:50 CET - Defending champion Jannik Sinner faces Felix Auger-Aliassime later tonight, but meanwhile, we are just minutes away from the clash between last year's runner-up Taylor Fritz and Lorenzo Musetti!
Follow the encounter live with Flashscore!
11:00 CET - Hello and welcome to the final chapter of the 2025 season with the ATP Finals in Turin continuing this afternoon. The first match of the day sees Lorenzo Musetti (who takes Novak Djokovic's place) take on world number six Taylor Fritz from 14:00 CET.
After losing to Djokovic in the final at Athens at the weekend, Musetti will be hoping to prove that he deserves his spot in this showpiece event by getting the better of Fritz in this intriguing Finals opener.
What will encourage the Italian is that Fritz has had an underwhelming end to the season on the ATP tour, only making it past one round in Basel and the Paris Masters last month.