Kevin Anderson defeated Sam Querrey to become the first South African to reach the semi-finals of a grand slam for 14 years.

The 31-year-old came out on top of a predictably tight encounter that finished just before 2am at Flushing Meadows, with Anderson winning 7-6 (7/5) 6-7 (9/11) 6-3 7-6 (9/7).

Not since Wayne Ferreira at the 2003 Australian Open has a South African made the last four at a slam, while Cliff Drysdale in 1965 was the last man to do so in New York, when the tournament was still amateur.

Anderson made his first grand slam quarter-final at the US Open two years ago but has been hampered by injuries since, dropping as low as 80 in the rankings in January.

He said: “This is incredible. Playing on this stage, one of the most famous courts in the world in a night session, getting through feels absolutely fantastic.”

In one of the most unlikely slam semi-finals of recent years, Anderson will take on Spain’s Pablo Carreno Busta for a place in the title decider.

Anderson was keen to savour his achievement before focusing on that challenge, saying: “This is very special for me, I’m going to try to enjoy it a little bit. 

“It’s going to be a tough battle but I’m just so excited to be competing in a semi-final of a grand slam.”

Earlier, Carreno Busta defeated Diego Schwartzman to reach his first grand slam singles semi-final.

The 12th-seeded Spaniard, the highest-ranked player left in the bottom half, proved too solid for his opponent, winning 6-4 6-4 6-2.

Meanwhile, Garbine Muguruza will become world No.1 on Monday after CoCo Vandeweghe continued America’s dominance of the women’s US Open by beating Karolina Pliskova.

The Czech needed to at least match her achievement of last year by reaching the final to prevent Wimbledon champion Muguruza overtaking her. 

She had a set point in the opener against Vandeweghe but could not take it and the 20th seed completed a 7-6 (7/4) 6-3 victory to reach her second grand slam semi-final of the season.

Vandeweghe joins compatriots Venus Williams and Sloane Stephens in the last four. Victory for Madison Keys over Kaia Kanepi later would make it the first clean sweep for the host nation since 1981.

“When I won this event as a junior I always dreamed about being here on the real stage,” said the 25-year-old. “To come together this year, it is a process. I did expect it overnight when I was 16 but now here I am and I couldn’t wish for anything better.

“I watched the match last night with Venus and think she said it best. We have to admire Serena and Venus, Lindsay [Davenport], Jennifer [Capriati]. 

“They all motivated me to be the next great American coming up and let’s make it four for four.”

Pliskova was the only top-eight seed to make it through to the quarter-finals and looked to have hit her stride after shaky early performances.