Italy's Jannik Sinner celebrates after winning the singles tennis match of the ATP World Tour Finals against United States' Taylor Fritz, at the Inalpi Arena, in Turin, Italy, Tuesday, Nov. 12, 2024. (AP Photo/Antonio Calanni)
Italy's Jannik Sinner returns the ball to United States' Taylor Fritz during their singles tennis match of the ATP World Tour Finals at the Inalpi Arena, in Turin, Italy, Tuesday, Nov. 12, 2024. (AP Photo/Antonio Calanni)
Italy's Jannik Sinner returns the ball to United States' Taylor Fritz during their singles tennis match of the ATP World Tour Finals at the Inalpi Arena, in Turin, Italy, Tuesday, Nov. 12, 2024. (AP Photo/Antonio Calanni)
Italy's Jannik Sinner holds the trophy as ATP world best player at the ATP World Tour Finals at the Inalpi Arena, in Turin, Italy, Monday, Nov. 11, 2024. Sinner was presented with the trophy for finishing the year ranked No. 1. (AP Photo/Antonio Calanni)
Supporters of Italy's Jannik Sinner cheers during the singles tennis match of the ATP World Tour Finals between Australia's Alex de Minaur and Italy's Jannik Sinner, at the Inalpi Arena, in Turin, Italy, Sunday, Nov. 10, 2024. (AP Photo/Antonio Calanni)
Italy's Jannik Sinner returns the ball to United States' Taylor Fritz during their singles tennis match of the ATP World Tour Finals at the Inalpi Arena, in Turin, Italy, Tuesday, Nov. 12, 2024. (AP Photo/Antonio Calanni)
Italy's Jannik Sinner holds the trophy as ATP world best player at the ATP World Tour Finals at the Inalpi Arena, in Turin, Italy, Monday, Nov. 11, 2024. Sinner was presented with the trophy for finishing the year ranked No. 1. (AP Photo/Antonio Calanni)
Italy's Jannik Sinner holds the trophy as ATP world best player at the ATP World Tour Finals at the Inalpi Arena, in Turin, Italy, Monday, Nov. 11, 2024. Sinner was presented with the trophy for finishing the year ranked No. 1. (AP Photo/Antonio Calanni)
Supporters of Italy's Jannik Sinner cheers during the singles tennis match of the ATP World Tour Finals between Australia's Alex de Minaur and Italy's Jannik Sinner, at the Inalpi Arena, in Turin, Italy, Sunday, Nov. 10, 2024. (AP Photo/Antonio Calanni)
A supporter of Italy's Jannik Sinner holds up a sign during the singles tennis match of the ATP World Tour Finals between Australia's Alex de Minaur and Italy's Jannik Sinner, at the Inalpi Arena, in Turin, Italy, Sunday, Nov. 10, 2024. (AP Photo/Antonio Calanni)