Jannik Sinner swats aside Christopher O'Connell to reach US Open fourth round

World number one Jannik Sinner's bid for a second Grand Slam title continued to gain momentum as he thumped Christopher O'Connell 6-1 6-4 6-2 to reach the US Open fourth round.

Sinner, who has seen two of his biggest rivals for the title at Flushing Meadow fall by the wayside after Carlos Alcaraz and Novak Djokovic were beaten, took an hour and 53 minutes to bundle out his 87th-ranked opponent.

"I try to stay on my side of the net and I'm trying to take it day by day," Sinner told reporters. "Each opponent is a very tough challenge. There have been already a couple of upsets, so let's see what's coming, but I'm very happy to be still here."

The Italian made slow starts in his opening two matches but he shot out of the blocks on Arthur Ashe Stadium court for a 5-0 lead before taking the first set on serve.

Australian O'Connell provided a degree of resistance in the second set, but Sinner broke early to take a 2-1 lead and went on to clinch the set with a searing crosscourt forehand winner.

Sinner continued to pepper O'Connell with winners, taking his tally up to 46 as he broke twice in the final set to wrap up victory with 23-times Grand Slam champion Serena Williams looking on from the stands.

Australian Open champion Sinner's strongest weapon in the victory was his flawless serve, firing 15 aces and denying O'Connell any break points.

"Today was a great match," Sinner said.

"I knew I had to play very solid throughout the whole match, and we played already a couple of times. I felt like today the serve was working really, really well.

Sinner, who has won seven straight matches since the start of his victorious campaign at the Cincinnati Open, faces either 14th-seeded local hope Tommy Paul or Canadian qualifier Gabriel Diallo in