Alex de Minaur has kept alive his faint hopes of reaching the season's ATP Finals climax with another resilient triumph at the Paris Masters.
Australia's top player had to come from a set down before finally outstaying and subduing the dogged Serb Dusan Lajovic 4-6 6-4 6-4 in a two-hour 11 minute slog in the Bercy hard-court event on Wednesday (Thursday AEDT).
The world No.13 must have a career-best run to the final of the season's last Masters event in the French capital to have any chance of leaping into the top-eight who'll battle in the Finals in Turin the week after next.
And though it remains a long shot, de Minaur knuckled down after a sluggish start to record another fine come-from-behind win, just as he did on Monday when he saved a match point against Andy Murray before prevailing in over three hours.
De Minaur made it another difficult afternoon for himself when, after not finding any trouble on serve in the opening set, he coughed up an easy missed volley at the net to gift the first stanza to the veteran Lavojic, who doubles as a successful coffee shop entrepreneur in Belgrade.
He'd never given de Minaur any trouble in their previous two meetings and had only got in the main draw as a lucky loser, but it took until the middle of the second set for the Australia to start to find the 33-year-old's measure with his first break - to love.
De Minaur reeled off 12 straight points at the end of the second set and the start of the third to take control, but after Lajovic hung in to break back, it needed another break to love to finally break the Serb's resistance.
De Minaur's win sets up a formidable last-16 contest against Jannik Sinner, the fourth seed, who defeated American Mackenzie McDonald 6-7 (6-8) 7-5 6-1.
De Minaur has a shocking record against Italian Sinner, having lost all five of their meetings, including a hiding in the final of the Canadian Open in August, the Australian's best run at a Masters event.
Alongside de Minaur, both Stefanos Tsitsipas and Hubert Hurkacz are still in contention for the three remaining spots at the ATP finals alongside the already-qualified Djokovic, Alcaraz, Medvedev, Sinner and Andrey Rublev.
Tsitsipas beat Felix Auger-Aliassime 6-3 7-6 (7-4), while Hurkacz cruised past Roberto Bautista Agut 6-3 6-2.