'Madness': Emma Raducanu shocks US Open in never-before-seen moment

Emma Raducanu has made tennis history, becoming the first qualifier ever to reach the semi-finals of the US Open.

The British 18-year-old produced yet another exquisite and astonishing performance on Wednesday, taking down Olympic champion Belinda Bencic 6-3 6-4 on Arthur Ashe Stadium.

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Raducanu's victory ensured to joins fellow teenager Leylah Fernandez in the last four.

Raducanu reached the Wimbledon fourth round on her grand slam debut just two months ago, and has so far won all 16 sets she has played from qualifying all the way through to the semi-finals in New York.

Down an early break, the Briton recovered swiftly to win four-straight games to close out the first set in which she cracked seven forehand winners.

Like Raducanu, Swiss star Bencic had reached the last-eight without dropping a set at Flushing Meadows but struggled with her first serve and misfired a pair of costly double faults in the opening set.

Raducanu maintained her momentum in the second set, fending off three break points in the second game.

A frustrated Bencic handed Raducanu a break with a double fault in the fifth game and her frustration boiled over as the match progressed, the Swiss smacking her racquet to the ground.

Down 0-30 in her final two service games, Raducanu kept her nerve on both occasions and soaked in the cheers of the New York crowd after triumphing in a nine-shot rally in the final point.

Raducanu's extraordinary performance follows that of Fernandez, who's just turned 19.

"To have so many young players here doing so well just shows how strong the next generation is," said Raducanu, who delighted a number of young fans by taking selfies with them before she walked off court.

"Everyone is on their trajectory. I'm just here taking care of what I can control, and it's my own journey at the end of the day.

"Playing Belinda - she's such a great opponent. Her ball speed definitely caught me off guard because she hits the ball so hard."

Tennis world in disbelief over Emma Raducanu 'madness'

Raducanu is just the fourth qualifier to reach a grand slam semi-final, making the Swiss 11th seed the highest-rated victim of her young career.

"It was a really tough match," Raducanu said. "I'm really glad to have come through."

But she had no perspective on her landmark achievement, having focused on tennis rather than milestones.

"I've actually got no idea about any of the records at all," Raducanu said.

"It's the first time I heard I was the first qualifier to make the semis. I had no idea before that.

"I'm not here to chase any records right now. I'm just taking care of what I can do on the moment and on the match ahead.

"Haven't even started thinking about the next one yet."

The tennis world could barely believe its eyes as Raducanu pulled off another ridiculous victory for someone so inexperienced on the grand slam stage.

Stuart Fraser said Raducanu’s run is “quite extraordinary” while Carole Bouchard tweeted: “Raducanu, this is madness”

Mike Dickson said it was “another day to rub the eyes in disbelief” and Victoria Chiesa said Raducanu's run was “just absurd”.

Jose Morgado pointed out that Raducanu will now jump to World No.51 (up from 338 before Wimbledon), replacing Johanna Konta as Britain’s No. 1 ranked player.

with AAP

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