'Frustrated' Ruud hit by illness at Roland Garros

Casper Ruud's hopes of advancing to a third successive Roland Garros final ended in a four-set defeat by Alexander Zverev on Friday as the Norwegian said he was laid low by a stomach bug.

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The two-time Roland Garros runner-up won the first set convincingly against Zverev before the German fourth seed fought back against an ailing Ruud to win 2-6, 6-2, 6-4, 6-2.

"It was a little bit unfortunate. I started well. Towards the middle, end of the first set, I started feeling some discomfort, an ache in my stomach," said Ruud.

"So I wasn't able to keep the intensity and the energy level up. It was something that was bothering me. Just kind of limiting me. It was a pity."

Zverev won just seven games in a resounding defeat by Ruud at the same stage of last year's tournament.

Ruud, who leads the tour with 39 wins this season, had been targeting his fourth major final but admitted he was not at his best physically.

"I won the first set, so it was a good feeling, but didn't feel very well even in the first set," he said.

"Then the last three went quick because Sascha played well, of course, but I wasn't able to play with the kind of tennis I like to play, with intensity, because I was kind of limited with my stomach.

"I don't want to make an excuse or excuses, but it's frustrating and disappointing."

Ruud had not played since Monday, receiving a walkover into the last four after Novak Djokovic withdrew ahead of their scheduled quarterfinal due to a knee injury.

"I (am) just, you know, disappointed that it had to be today. Why couldn't it be yesterday or day before when I had three days off."