Novak Djokovic moved one step away from a sixth Paris Masters title by beating Hubert Hurkacz, guaranteeing himself the year-end number one ranking for a record seventh time.
The Serbian great is looking to get back to title-winning ways in his first tournament since September, when his hopes of a calendar Grand Slam were snuffed out by Daniil Medvedev in the US Open final.
He was pushed all the way to a deciding set tie-break by world number 10 Hurkacz, the player who beat Roger Federer at Wimbledon amid his breakout year.
But Djokovic had just enough in the tank to complete a 3-6 6-0 7-6 (7-5) semi-final victory, thumping his chest in relief and exhilaration as he got across the winning line.
On Sunday, he will bid to set another record by moving ahead of Rafael Nadal to reach 37 titles in Masters 1000 tournaments.
Saturday's success guarantees Djokovic will end the season on top of the ATP rankings for a record-breaking seventh time – Pete Sampras drops to second on the list with six years at the top.
Hurkacz broke serve in the eighth game of the first set and closed it out, only to surrender meekly in the second.
Djokovic broke to lead 3-1 in the decider, but a spirited Hurkacz recovered the break with a booming forehand into Djokovic's backhand corner in the seventh game.
The Polish player staved off a match point when serving at 5-4, getting somewhat lucky when a Djokovic passing shot landed just wide.
A tense tie-break swung Djokovic's way when Hurkacz lashed a forehand into the net at 5-5, and a backhand volley from the Miami Masters champion landed just wide on match point.
In the title match, Djokovic will tackle the winner of the second semi-final between Medvedev versus Alexander Zverev.