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 will contest his seventh Paris Masters final on Sunday, having won five of his previous six.
He will face the winner of the match between Tokyo Olympic champion Alexander Zverev and reigning champion Daniil Medvedev.
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.