Novak Djokovic claimed a record seventh year-end number one ranking by overcoming Poland's Hubert Hurkacz to reach the Paris Masters final.
Hurkacz, 24, won the semi-final's first set but was outplayed in the second.
In a nervy deciding set, Djokovic, 34, won on his second match point to prevail 3-6 6-0 7-6 (7-5).
That victory meant the Serb surpassed Pete Sampras's record for the most year-end rankings and now has two more than Roger Federer and Rafael Nadal.
Djokovic said he was "just proud and extremely happy" with the achievement.
"Obviously that was one of the biggest goals, and it's always one of the biggest goals, to try to be number one and end the season as number one," he added.
"To do it for the record seventh time and surpass my childhood idol and role model Pete is incredible. Very grateful, very blessed to be in this position."
Djokovic will contest his seventh Paris Masters final on Sunday, having won five of his previous six.
He will face reigning champion Daniil Medvedev, who beat Tokyo Olympic champion Alexander Zverev in the other semi-final.
Djokovic is making his return to the tour for the first time since being beaten by Medvedev in the US Open final in September.
That defeat left the Serb in tears when his dream of becoming the first man in more than 50 years to win all four majors in the same season was dashed.
He remains tied at 20 Grand Slam titles with Federer and Nadal.
Medvedev, 25, eased past last year's losing finalist Zverev, stifling the German in a 6-2 6-2 victory.
The Russian made the match uncomfortable for Zverev, 24, who had been the in-form player on the tour, coming into this match with 28 out of 30 wins since Wimbledon.
Zverev looked to struggle the longer the rallies went on, as Medvedev used the slower conditions to his advantage.
Medvedev will attempt to defend a title for the first time. Sunday's final will be his 10th tour-level encounter with Djokovic, with the Serb leading the head-to-head 5-4.
Earlier in the day, the British-Brazilian pairing of Jamie Murray and Bruno Soares fell in the semi-final, losing to Tim Puetz and Michael Venus 7-5 6-3.
However they have qualified for the doubles event of the ATP Tour Finals, which start on 14 November in Turin, as has Britain's top-ranked doubles player Joe Salisbury with his US partner Rajeev Ram.