Nadal out as Tiafoe crushes second seed in major US Open upset

American Frances Tiafoe played the match of his life to beat second seed Rafa Nadal 6-4 4-6 6-4 6-3 in the fourth round of the US Open.

It was the first time this year that Nadal, who had been chasing a record-extending 23rd Grand Slam title, has been beaten in a major.

Tiafoe covered his face with his hands as he soaked up the cheers from a packed house at Arthur Ashe Stadium after breaking Nadal for a fifth time to claim the biggest upset of the tournament.

"I don't even know what to say right now, I'm beyond happy, I'm almost in tears," Tiafoe said in an on-court interview on Monday.

"I can't believe it. He is definitely one of the greatest of all time. I played unbelievable tennis today but I really don’t know what happened."

Next mission: Rublev

While Tiafoe did indeed play sublime tennis, he also benefited from an uncharacteristically poor serving and returning performance from Nadal.

The Spaniard produced nine double faults and hit just 33 winners to Tiafoe's 48.

With the win, Tiafoe snapped Nadal's streak of 17 straight majors where he reached the quarter-finals or better. 

The Spaniard had triumphed at the Australian and French Opens this year before withdrawing with an abdominal injury before his semi-final at Wimbledon.

Next up for Tiafoe is a quarter-final showdown with Russian Andrey Rublev.

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