'Can't believe it': Ash Barty suffers meltdown in US Open shocker

World No.1 Ash Barty (pictured left) becoming irritated during her match against Shelby Rogers and Barty (pictured right) leaving Arthur Ashe Stadium.
World No.1 Ash Barty (pictured) was knocked out of the US Open after losing to Shelby Rogers in the third round. (Images: Getty Images/ESPN)

World No.1 Ash Barty was unable to close out the match against American Shelby Rogers and has been knocked out of the US Open in the third round.

The World No.1 entered the match as the strong favourite, but quickly fell behind after an uncharacteristically poor start.

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Despite holding such a strong record against the American this year, Barty played one of her worst sets of tennis in some time after serving five double faults and hitting 17 unforced errors.

The American ran away with the set 6-2 in 35 minutes.

Remarkably, the commentators pointed out Barty was able to 'flick a switch' during the set break and come out to take the second set in barnstorming fashion.

Barty then took a 5-2 lead in the final set and had two opportunities to serve out the match.

But, her struggles serving for the win continued and Rogers broke twice to send the decider into a tiebreak.

And after a some high-quality baseline hitting from both opponents, Rogers was able to earn the mini-break and win 6-2, 1-6, 7-6 to set up a showdown with British teen sensation Emma Raducanu.

Barty showed her usual class when greeting her opponent at the net, but the tennis world was left utterly shocked at the World No.1's horror collapse in the final set.

While the World No.1's serving was pinpointed as one of her secret weapons leading into the US Open, closing the match on serve ultimately was her downfall.

Emma Raducanu stuns tennis world

Rogers will now face British teen Raducanu.

The 18-year-old Raducanu, who burst onto the scene earlier this year by reaching the fourth round at Wimbledon in her first Grand Slam appearance, was utterly dominant against Spain's Sara Sorribes Tormo, closing out the one-sided match 6-0, 6-1 in 70 minutes.

The rising star became the youngest British woman to advance to round four of the US Open since 2012.

Raducanu, who came to New York ranked 150th in the world, has breezed through all three of her matches without dropping a set and won a hugely impressive 79 per cent of her first-serve points while smashing 23 winners past her hapless opponent.

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