The patrons were hanging from tree branches around Court No7 to get a better look and there was a sense that any moment Sir David Attenborough would burst through the foliage having unearthed what was considered an endangered species - the British woman tennis player who reaches the third round in the jungle that is Flushing Meadows.

Not since 1991, when Jo Durie and Sara Gomer blazed a two-pronged trail, has a British female been as deep into the US Open - Durie went a round farther before falling to Jennifer Capriati - and let no one say that Anne Keothavong did not thoroughly merit the ovation that poured down upon her when Francesca Schiavone, of Italy, the world No25, double faulted on match point. Isn't that what Britons usually do?

Keothavong won 6-2, 3-6, 6-4 in 2hr 28min and when the fire was at its most intense, it was the No87 and not the former US Open quarter-finalist who nailed the lines and played the more steadfast tennis. From 4-2 down in the final set, she reeled off the last four games, although two foot faults by Schiavone and an umpire's overrule on the baseline against her in the eighth game were hardly designed to quell Italian combustibility.

Give Keothavong enormous credit. She required seven set points and saw off four break chances to win the opening set, and her forehand creaked for the first time in the fifth game of the final set when Schiavone broke serve and ought to have gone on to make her greater experience and nous tell.

But the 24-year-old from Hackney, East London, urged on by her parents and extended family, was resolute and focused. She was the one peppering the corners, forcing Schiavone to err off the ground. She was the one who did not appear consumed with doubt, she was the one who served better when it was required, she was the one whose shot selection was more precise. Now she has to do all that and more against Elena Dementieva, the Olympic gold medal-winner from Russia and twice a grand-slam tournament finalist.

Whether it ends there or not, Keothavong's results here have been a real boon. This was the first time that her ranking - it will rise to the top 70 - had been high enough to grant direct entry into a grand-slam tournament abroad and her game is in the best shape ever. These are the places where the professionals are judged and Keothavong had been plodding around the nether regions of the game for the best part of a decade, putting together the odd victory here and there, hoping that she would finally get on a significant roll.

So much of what happens in British women's tennis - until a 14-year-old phenomenon such as Laura Robson comes along - is distinctly small print, but as Keothavong said: “It's nice to give Andy Murray some company in these events and share the limelight with him. I'm in the third round of a grand slam for the first time, but I don't want to stop now.

“Breaking into the top 100 [three months ago] was a goal that kept me going - it just took me a lot longer than many players. I knew that if I kept working, it would happen.”

Keothavong and her coach, Claire Curran, along with Nigel Sears, the Great Britain Fed Cup captain, will be back in their favourite French restaurant tonight, ordering the crème brulée as a treat.

Back home, interest was immense - perhaps more for the novelty value of someone else to talk about rather than Murray. The BBC Radio team commentated on the whole match, although they could see the court thanks only to a camera perched at an obscure angle that did not often allow for definitive judgments as to whether the ball was in or out. When a wasp landed on the camera lens, it was impossible to see what was going on, but the team soldiered on. As does Keothavong.