Jannik Sinner outlines how conditions change from day to night at the Cincinnati Open

Photo by Clive Brunskill/Getty Images

Jannik Sinner outlines how conditions change from day to night at the Cincinnati Open

Originally posted on HITC | By Liam Llewellyn | Last updated Aug 12, 2025 6:59 AM ET

Jannik Sinner is still in the hunt to retain his Cincinnati Open title, coming through a challenging encounter against Gabriel Diallo. The Italian is playing his first tournament since July when he defeated Carlos Alcaraz to win Wimbledon.

Sinner started his Ohio campaign with a dominant 6-1, 6-1 victory over qualifier Daniel Galán. But the match against Diallo was far less straightforward.

The Canadian pushed Sinner into a second-set tiebreak and even held a set point. But the world number one responded by winning the next three points to secure a hard-fought win.

Jannik Sinner notes the difference in ball movement at night during Cincinnati Open

One of the defining features of the Cincinnati Open is how quick the courts can play, often favouring players with big serves and powerful groundstrokes.

The hard courts at the Ohio-based ATP and WTA 1000 events suit the big servers and hard hitters, and Sinner was up against a stronger serve in Diallo under the lights on the P&G Center Court.

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Diallo served ten aces and made a higher percentage of first serves than Sinner, but he committed 10 double faults and struggled on his second serve, winning just 23% of points.

Sinner took advantage of the fast conditions by producing aggressive returns to put his opponent immediately under pressure in rallies. This is exactly how he saved set point in the second set tiebreak before completing a 6-2, 7-6(6) victory.

Sinner’s win over Diallo was his first evening match of this year’s tournament. Speaking afterwards, he highlighted how playing conditions can change between day and night sessions.

“The other day I had to play during the day session and today it was at night,” Sinner said. “The ball still flies a lot, too much even if it felt slightly less so tonight.”

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“Even so, these matches we play at night are an improvement compared to those played during daylight hours,” he added.

“Now I have to prepare for another difficult test in similar conditions. The main thing will be to stay mentally strong again.”

Jannik Sinner describes match against Gabriel Diallo as a ‘tough day at the office’

The Cincinnati Open was the first meeting between Sinner and Diallo, and despite taking the opening set comfortably, the world number one had to dig deep in the second to avoid being pushed to a decider.

Sinner, who faces Adrian Mannarino next, was pleased to come through in straight sets and welcomed the early test with bigger challenges ahead.

“It was a tough match, it felt like a very difficult day in the office. I think he served unbelievably all the time, but especially in the second set,” said Sinner.

“When facing these types of opponents, who are great servers, you always have to find a certain balance from the back of the court, which can take some time.”

“In that sense, today I had problems during many phases of the match, but right now I am happy with the result.”

Sinner added: “In the end this is what I was looking for. I need matches as tough as this; being immersed in adverse situations during games.”

This article first appeared on HITC and was syndicated with permission.

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