Fatigue does not explain Alexander Zverev’s surprise semi-final loss at the 2026 Shanghai Masters, according to a renowned commentator and former player.

World No 2 Zverev was upset 5-7, 6-4, 6-3 by world No 26 Alejandro Davidovich Fokina in the last four in Shanghai on Saturday.

Zverev was the top seed in Shanghai, and he became the clear favourite to win the title at the Masters 1000 event after second seed Carlos Alcaraz‘s third round loss to Zizou Bergs.

The German, who won the French Open and US Open this year, is guaranteed to replace the injured Jannik Sinner as the world No 1 before the end of 2026.

The 29-year-old cited tiredness as a factor for his loss in Shanghai when asked what made the difference.

“I mean, I think, first, I’m not a robot, I’m a human being (smiling), I get tired. It’s like this,” said Zverev.

“After the US Open, I had one day off in total. I think I played a lot of tennis, which is very, very positive because that means I played well.

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“I think even here I had tough matches. I personally feel like I was quite flat since the Bublik match, because I was losing energy.

“I played a phenomenal match against Alex de Minaur, but today I was flat. Even in the first set, even though I won the set, I was flatter, I was not reacting so well.

Nick Lester and Rob Koenig discussed whether fatigue could be blamed for Zverev’s loss after commentating on the match for Tennis TV.

Lester posed a series of questions to Koenig: “What did you make of his (Zverev’s) performance today? Was there any element of tiredness?

“Do you think the season has caught up with him a little bit today? Or, are we making excuses?”

Koenig, a former ATP player, argued Zverev’s failure to return Davidovich Fokina’s wide serve to his forehand could not be a result of tiredness.

“I think the reason for all those forehand misses… you can’t really blame fatigue on return of serves,” said Koenig.

“He just couldn’t come to grips on the deuce side. This guy (Davidovich Fokina) was playing 15-0 up in just about every service game.

“On the return of serve front, that’s where Zverev will be so disappointed.

“For the first time, [Davidovich Fokina] has won more than 80% of the points behind that first serve against Zverev.”

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