Defending men’s champion Jannik Sinner is through to the last 16 of the Cincinnati Open after a 6-2 7-6 (8-6) victory over Canadian Gabriel Diallo.

It was a match not without drama as a fire alarm delayed proceedings before Sinner extended his winning run to 23 matches.

Next up, he will face Adrian Mannarino after his 5-7 6-3 6-4 win over Tommy Paul.

While it was another tick in the victory tally, Sinner found the contest “difficult” and he admitted he was glad he found it so tough in Cincinnati and not at the upcoming US Open.

“I feel like today was a very difficult day at the office,” Sinner said. “He was serving very well, especially in the second set. Against big servers you always have to find the right balance at the back of the court.

“Today I struggled a bit at times. But still very happy. I need these tough matches… getting used to very difficult situations. I’m very happy this happened before a Grand Slam.”

The drama of the fire alarm in Sinner’s contest was proceeded by a suspension in play for a little more than an hour due to a power outage.

The delay came at 5.25 p.m. after Taylor Fritz won the opening set on centre court 7-6(7-4) against Lorenzo Sonego. Play resumed shortly before 6.40pm.

Fritz went on to claim a straight-sets 7-6(7-4) 7-5 win following the delay and remarkably did not face a break point in the match that lasted just over two hours.

Elsewhere, former champion Madison Keys made it through to the last 16 with a 6-4 6-0 win over Japan’s Aoi Ito.

Watch the Cincinnati Open up until August 18 before we head to the US Open in New York for qualifying and the main draw from August 24 at 3pm, live on Sky Sports or stream with NOW and the Sky Sports app, giving Sky Sports customers access to over 50 per cent more live sport this year at no extra cost. Find out more here.