Jannik Sinner records a first win over Novak Djokovic at ATP Finals

Jannik Sinner came of age at the ATP Finals in Turin with a first career victory over world number one Novak Djokovic.

The 22-year-old Italian won a three-hour marathon 7-5 6-7 (5-7) 7-6 (7-2) in a match of high tension and tremendous quality.

Defending champion Djokovic next faces Poland's Hubert Hurkacz on Thursday in his final group match as he bids to reach the semi-finals.

In front of a raucous home crowd, Sinner grabbed the crucial break in the 11th game, despite finding himself 40-0 down, and then held to love to take the first set.

Djokovic, on a 19-match winning streak, took the second set to a tie-break and was twice a mini-break down before levelling the match, cupping his ear to the spectators.

World number four Sinner then played a stunning return game, breaking Djokovic to 15 with a punishing forehand to move 4-2 up in the third.

But with two hours and 40 minutes on the clock, Djokovic finally broke his young opponent for the first time in the match.

At 5-6 Djokovic began conducting the jeering crowd from his seat at the changeover.

The six-time ATP Finals champion had won 30 tie-breaks this season but number 31 proved elusive as Sinner moved 5-0 up before sealing a statement win with a smash.