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Sinner was not at his free-flowing best against Mannarino but had too much for the Frenchman either side of the two-hour, 45-minute rain delay that arrived at the start of the second set. In a tight opening set, the No. 1 player in the ATP Rankings produced a moment of magic on return at 4-2 when he tracked down a Mannarino smash before striking a backhand winner from deep in the court.

The Italian made just 52 per cent of his first serves in the match and struggled to find his timing from the baseline in the second set against the clean-hitting Mannarino. However, after failing to serve out the match at 6-5, the 23 year-old remained composed in the tie-break to triumph.

"He is a very tough opponent. Very different from other opponents, not only because he is a lefty but how he hits the ball. It is very low," Sinner said. "I just tried to serve well and tried to see what I could do in the return games.

"He was serving very well, especially on the Ad side, on the wide one was very precise. I changed the position, trying to make him feel uncomfortable. I struggled a bit to close it out, but this can happen in this sport and I am very happy to be in the next round."

With his one-hour, 48-minute victory, Sinner extended his winning streak on hard courts to 24 matches, surpassing Novak Djokovic’s 2015 run of 23 wins and climbing to eighth place on the list of the longest hard-court winning streaks of this century. The Italian’s last defeat on the surface came against Carlos Alcaraz in the Beijing final last October.

Sinner will next meet 23rd seed Felix Auger-Aliassime in his fifth quarter-final of the year. The 23-year-old has won his past 21 matches against French players.

Playing his first tournament since winning his first Wimbledon title, Sinner is 29-3 on the season. Just eight wins away from 300 career victories, Sinner earlier in the month became the second player to qualify for November's  ATP Finals, joining Alcaraz.

Sinner and Alcaraz will compete in a thrilling battle for ATP Year-End No. 1 honours over the remaining months of the year. Alcaraz  holds a 1,440-point lead over Sinner in the ATP Live Race To Turin.

Mannarino upset Tommy Paul to advance to the fourth round at a Masters 1000 event for the first time since he reached the quarter-finals in Cincinnati two years ago. The 37 year-old found joy with his lefty serve out wide on the Ad court against Sinner, but his resistance was eventually broken in the second-set tie-break. Mannarino moved up 18 spots to No. 71 in the ATP Live Rankings.