US Open: Jannik Sinner beats Christopher O'Connell to reach fourth round

Sinner is the only men's top-three seed to make it into the second week after shock defeats for defending champion Novak Djokovic and Spanish star Carlos Alcaraz, and he did it in efficient style.

Sinner fired 15 aces with a total of 46 winners and didn't face a break point, bringing home the win in less than two hours.

He has now advanced to the fourth round of all Grand Slam events in a season for the second time in his career.

The 23-year-old Italian will face either Canadian qualifier Gabriel Diallo or 14th-seeded American Tommy Paul with a chance to match his best US Open performance, a quarter-final run in 2022.

"Today was a great match," he said. "I felt like today the serve was working very very well."

Sinner also made a point of thanking the Arthur Ashe Stadium crowd for their support.

Not all of his tour rivals have sounded convinced after it was announced this month he had escaped a lengthy suspension despite twice testing positive for a banned anabolic agent back in March.