Novak Djokovic has extended his winning streak to 20 at the Paris Masters on Friday, defeating Tomas Berdych 7-6 (7-3) 7-6 (10-8) to reach the semi-finals.
Andy Murray and David Ferrer also made it through to the last four in the bottom half of the draw on a day of marathon clashes, but Rafael Nadal crashed out to Stan Wawrinka.
The straight sets victory for world No.1 Djokovic also meant he has now won 28 sets in a row – the best run of his career – dating back to the US Open final in September.
But he had a battle on his hands against fifth-seeded Berdych, a winner in Paris 10 years ago when he was just 20.
Neither player could manage a break of serve, the first time that has happened to Djokovic in 680 career wins, according to ATP statistics.
“It was decided in tiebreaks two times, and very few points, really, decided a winner today, Djokovic said.
“Could have gone a different way. He had set point in the first set, as well. In the important moments, I just managed to hang in there, you know, just stay tough. That’s what I’m most proud of.”
Djokovic will next play Wawrinka, who sent Nadal packing 7-6 (10-8) 7-6 (9-7) the Swiss having defeated him the last time the two men met in Paris in the French Open final in June.
That defeat prevented Djokovic from accomplishing the fabled calendar year grand slam which only two men – Rod Laver and Don Budge – have ever achieved before.
He won the Australian and US Opens as well as Wimbledon.
The other semi will oppose second seed Murray against 2012 champion Ferrer.
Murray made the last four of the Paris indoors for the first time, but it needed a marathon effort to see off the last remaining Frenchman, Richard Gasquet.
The second seed, who had dropped just four games in reaching the last eight, was kept hard at it for two hours 38 minutes before edging through 7-6 (9-7) 3-6 6-3.
Five times previously Murray had fallen in the quarter-finals of the ATP’s regular season finale.
The win meant that Murray joined Roger Federer, Nadal and Djokovic as the only players to reach the semi-finals or better at all nine of the Masters 1000 Series tournaments during their career.
Ferrer, who won the 2012 tournament in Paris defeated John Isner 6-3 6-7 (6-8) 6-2.