Emma Raducanu had a flight home booked before the US Open proper had even begun but the British teenager is now two victories away from one of the most extraordinary achievements in tennis history.

The 18-year-old defeated 11th seed Belinda Bencic 6-3 6-4 to reach the semi-finals, making it three qualifying victories and five in the main draw, all without dropping a set.

She will play 17th seed Maria Sakkari for a place in the final, following the Greek’s 6-4 6-4 quarter-final win over fourth seed Karolina Pliskova, this year’s Wimbledon runner-up.

Raducanu is the first qualifier ever to reach the last four and, having passed her biggest test so far with a comfortable victory in her first career match against a top-20 player, she is a genuine contender for the title.

“I have known Leylah since we were juniors, in under-12s,” said Raducanu. “I played her in Junior Wimbledon.

“The fact that we are both here in the semi-finals of the US Open after having played each other from the early days, it’s very cool to see just how far we have come.”

Sakkari, 26, paid tribute to Raducanu but voiced confidence in her chances against the teenager.

“We have many young girls playing well right now. Emma is having a great run but I trust my game and believe in myself,” she said.