Jannik Sinner is the defending champion and a three-time qualifier for the Nitto ATP Finals.

After a groundbreaking 2024 season, Sinner has maintained his form, winning major trophies at the Australian Open and Wimbledon. It is the second consecutive year in which he has earned two Slam trophies.

Sinner first competed in the season finale as an alternate in 2021 and then returned as a first-time qualifier in 2023. He has won nine of his past 10 matches at the event, reaching the final in 2023 and claiming glory in 2024.

The home favourite will have an opportunity to become the first player outside of Novak Djokovic to successfully defend the Nitto ATP Finals since Roger Federer did it in 2011.