Ben Shelton downs Jannik Sinner to reach quarter-finals at Shanghai Masters

Sinner upset Carlos Alcaraz and Daniil Medvedev to win the China Open title in Beijing last week but, the day after his 21st birthday, Shelton powered to victory over the world number four.

The young American was ranked down at 160 this time last year but it has been a breakthrough season, with an Australian Open quarter-final appearance followed by a run to the last four at the US Open.

This is his best week outside the slams and, after coming from a set down to edge the contest in a deciding tie-break, Shelton reprised his telephone celebration from New York.

"This is a pretty crazy atmosphere," he said. "To think that a year-and-a-half ago I was in college and a year ago playing Challengers, now I am on centre court in Shanghai with the crowd singing happy birthday. It is one of those pinch-me moments."

In the last eight, Shelton will take on fellow American Sebastian Korda, who defeated Francisco Cerundolo 7-5 7-6 (6).

There was another upset when Hungary's Fabian Marozsan knocked out eighth seed Casper Ruud 7-6 (3) 3-6 6-4 for his second big win of the week following his second-round victory over Alex De Minaur.

READ MORE: Carlos Alcaraz through to fourth round of Shanghai Masters after battling past Dan Evans