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Griekspoor earned the biggest win of his career in the process, and the Dutchman had been on the verge of an exit himself after Zverev fought back from 2-5 to 6-5 in the second set, giving himself a serve out for the match.

But the German was unable to convert that opportunity, as Griekspoor forced and won a tiebreak to take it to a decider.

After failing himself to convert five match-points on serve at 6-5 in that set, Griekspoor eventually won the tussle in another tiebreak, converting his sixth match point of the contest to move through.

"It was such a mental thing," Griekspoor said, referring to his match-ups with Zverev.

"I lost to him five times last year and had absolute heartbreak at Roland Garros where I was up a double break in the fifth.

"I played so many battles against him and had chances but they all went his way. I am incredibly proud of myself from this performance and to get it over the line."

Zverev, who was competing for the first time at Indian Wells as its No.1 seed, had a chance to close the gap on world No.1 Jannik Sinner with a winhere, but still trails the currently suspended Italian by 3385 points as a result of his shock exit.

But Zverev will hold on to the No.2 spot, even if world No.3 Carlos Alcaraz defends his title in this tournament.