Novak Djokovic beat Tallon Griekspoor in straight sets in the Geneva Open quarter-finals on Thursday, teeing up a last-four meeting with Tomas Machac.

Djokovic was pushed all the way in an intriguing opener, Griekspoor generating three set points only to fail to convert any of them.   

The world number one immediately punished Griekspoor's wastefulness by breaking at the end of a back-and-forth service game, then proceeded to serve the first set out in comfort.

Griekspoor would not get a second chance to make a contest of it as Djokovic took full advantage of an early break in the second set, serving at 81 per cent and winning 92 per cent of points behind his first serve from there as he cruised to a 7-5 6-1 win.

Data Debrief: Age just a number for Djokovic

Having turned 37 on Wednesday, Djokovic is the oldest semi-finalist in Geneva Open history.

Now 14-5 for the year, he is the strong favourite to claim his first title of 2024. Flavio Cobolli will face Sebastian Baez or Casper Ruud in the other semi-final.