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Zverev triumphed 3-6 6-4 6-2 4-6 7-6 (10-3) at the end of a gruelling four-hour, 17-minute contest on Court Philippe-Chatrier, teeing up a Round of 16 meeting with Holger Rune or Jozef Kovalik.

Zverev looked to have weathered an early storm when he fought back after losing the opener to go 2-1 up, but Griekspoor refused to go away and came roaring back in the fourth set, which lasted almost an hour.

The world No.4 appeared to be up against it when he was broken in the first game of the decider, and his frustrations got the better of him as he yelled at the umpire before being broken again.

However, he immediately hit back with two breaks of his own to go from 4-1 down to 4-4, eventually forcing a decisive tie-break.

He found another gear from there, sapping Griekspoor's confidence with some excellent play at the net, with a fine passing shot past his stranded opponent a highlight before he clinched victory with an ace. 

Having warmed up for Roland Garros by winning the Italian Open, Zverev has now won nine straight matches on clay for the first time since 2018, when he won 13 consecutive contests on the surface at Munich, Madrid and Rome.