Novak Djokovic won a record seventh ATP Finals title with a dominant victory over Jannik Sinner that marked another milestone in his memorable season.
The Serb, 36, who lost to the Italian in the group stage, avenged that with a 6-3 6-3 win in Turin, Italy.
He has set records in rankings and titles this year and played some of his best tennis against the youngsters - like Sinner - trying to challenge him.
The world number one had been tied with Roger Federer on six ATP Finals wins.
But it was clear from the outset in Sunday's final that he was hungry to take the outright record, establishing control with an early break and dropping just two points on his serve in an almost flawless display to take the opening set.