Alexander Zverev's slump continues with shock Indian Wells exit to Griekspoor

World No 1 Jannik Sinner's absence in Indian Wells and Miami opened the door for World No 2 Zverev to close the gap on at the top of the rankings, but he has endured a miserable run of form in recent weeks.

Food poisoning impacted Zverev's performances as he played on clay courts in South America in recent weeks, but he arrived in Indian Wells talking up his hopes of hitting top form on hard courts he generally performs well on.

Yet Griekspoor added another big name to his list of victims as he backed up his win against Daniil Medvedev in Dubai last month with another win against a top ten opponent as he beat Zverev 4-6, 7-6(5), 7-6(4).

"It was such a mental thing. 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," said Griekspoor.

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

"I had some ankle problems from the first match and I didn't know how it was going to be today. I felt it was pretty warm as well, over three hours. I am proud of myself with my mental and physical performance."

Zverev's defeat denied him a chance to take a bite out of Sinner's lead at the top of the ATP Rankings, with the German now losing four of his last eight matches since the Australian Open.

"I'm just playing terrible," admitted Zverev after the match.

"For me, I have to find my game before thinking about that, because to become world No. 1, you have to win tournaments. I'm not past getting first, second round at the moment. So I need to figure that out first.

"I can sit here and have excuses, but at the end of the day I'm just not playing good tennis at the moment. It's as simple as that.

"I'm not playing a level that I want to play, definitely not playing anywhere near what I played in Australia. This is the end result of, I don't know, yeah, maybe Australian Open. But I'm just, yeah, I'm just disappointed with my game. That's No. 1 thing for me."

That is a worrying run of form for a player with his lofty ranking and it ensures he will remain more than 4,000 ranking points behind Sinner.

His defeat also gives Carlos Alcaraz a chance to trim the points gap with Zverev, as he aims to ensure he is among the top two seeds for the second Grand Slam of the year at the French Open.

The bigger concern must be the collapse in form for Zverev, after his powerful serve was broken five times by Griekspoor, who fired more aces than his rival by 10 to six as he confirmed once again that he can be a giant killer on the ATP Tour.

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