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.
"One of the best seasons I've had in my life, no doubt," Djokovic said.
"It's very special. To crown it against a hometown hero in Jannik this week is phenomenal," he added in comments to Amazon Prime.
"Tactically I played differently today than in the group stage against Jannik. Overall, a phenomenal week."
Before the singles final, there was British success in the doubles when Joe Salisbury and American partner Rajeev Ram retained their title with a straight-set win over Marcel Granollers and Horacio Zeballos.
Djokovic 'steps it up' against Sinner
World number one Djokovic had been tied with Roger Federer on six ATP Finals title wins, but it was clear from the outset in Sunday's final that he was hungry to take the outright record.
He established control with an early break and dropped just two points on his serve in an almost flawless display to take the opening set.
A break to love in the opening game of the second set put Djokovic further ahead and made Sinner's dream of becoming the event's first Italian champion in front of a noisy home crowd seem impossible.
Sinner's first break-point chances came in the sixth game of the second set when he went 15-40 on the usually impenetrable Djokovic serve, but the 24-time Grand Slam champion swiftly snuffed out the threat by forcing his opponent into errors from the back of the court.
Djokovic had the chance to go a double break up in the following game but, in a rare moment of fallibility, instead missed a straightforward volley before Sinner held with an ace.
But he got his chance in the Italian's next service game, with Sinner tamely handing over victory with a double fault on Djokovic's first match point.
It was a far cry from the Italian's performance against the Serb on Tuesday, when a victory in three sets ended Djokovic's 19-match winning streak.
But this was also a different Djokovic to then, with the Serb building on the brilliant performance he put in against world number two Carlos Alcaraz in Saturday's semi-finals to deliver an outstanding display underpinned by him winning a huge 91% of first-serve points.
"The way Carlos and Jannik have been playing, I had to step it up," said Djokovic, who must now surely go into next season as favourite to dominate yet again and strive for yet more records.
Djokovic hits another milestone in a record-setting year
This year has been full of records for Djokovic and so it seems only fitting that his tour season should end with another at an event where he was already its oldest champion.
Sunday's victory pulled him ahead of Federer for titles won at the ATP Finals, while he was confirmed as year-end men's world number one for a record-extending eighth time earlier in the tournament.
This year he also surpassed Steffi Graf's record for the most weeks spent at the top of the singles rankings, with his tally now about to stand at 400 from Monday.
Djokovic won three of this season's four Grand Slam singles titles to overtake Rafael Nadal's men's tally of 22 and draw level with Australian Margaret Court's all-time record of 24.
That included a record-extending 10th title at the Australian Open - which is where in January he will get the chance to become the outright record holder with a 25th major.
His French Open victory in June made him the only man to win a career Grand Slam - all four major titles - three times.
And this year he also set a record for most Grand Slam final appearances with 36, two more than Chris Evert's previous mark, and earlier this month he won a record-extending seventh Paris Masters trophy for a record-extending 40th Masters title.
While his tour season is over, Djokovic's playing season continues next week at the Davis Cup Finals in Malaga, Spain, where he will lead Serbia in their quarter-final against Great Britain on Thursday - a tie which you can watch on the BBC and follow with live text commentary on the BBC Sport website.
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