Johanna Konta has reached the third round of the US Open with a dramatic victory over Bulgaria's Tsvetana Pironkova, despite collapsing at one stage with heat exhaustion.
The 13th seed seemed to be cruising as she took the first set 6-2, but during the second the combination of heat and humidity took its toll, and when she had to serve at 5-6 down to take the second set to a tie-break the Briton started to struggle with her breathing. At set point down, she collapsed on the court and called an immediate medical time-out.
A five-minute spell of treatment with ice helped cool her down, with the player revealing afterwards that she had felt her heart rate spike and started shivering.
Having managed to resume, Konta lost the set point but then took the opportunity for a bathroom break and a chance to change clothes. When she returned, Pironkova lost momentum as a result of the delays and while Konta was not feeling at her best, a series of canny groundstrokes saw her outfox the Bulgarian and take the deciding set 6-2 to secure a clash with Belinda Bencic of Switzerland in the next round.
Konta said of her collapse afterwards: "It was basically very embarrassing. I started hyperventilating. I started shaking. That's why I went down on the ground, because I was quite violently shaking." She also revealed she knew what the problem was, because she had suffered a similar on-court problem in a match in 2014.
However awkward the British number one may have felt, her steel in being able to come through such a situation was another sign of how her mental toughness has increasingly been allied with her wide range of skills as she has climbed the rankings. It is another reason for those booking corporate hospitality for The Championships, Wimbledon to have high hopes of a British female singles champion before long.
Konta's hopes in New York were boosted by the exit of French Open champion Garbine Muguruza. The third seed was beaten 7-5 6-4 by Latvia's Anastasija Sevastova.
Muguruza was not the only big name to fall. In the men's draw, Wimbledon finalist Milos Raonic lost in four sets to American qualifier Ryan Harrison. Like Konta, he had also suffered in the heat as cramp wrecked his chances.
The weather caused no problems for Kyle Edmund, who followed his first-round thrashing of 13th seed Richard Gasquet with another straight sets win against Ernesto Escobedo to set up a third round clash with John Isner. Britain's leading doubles player Jamie Murray and Brazilian partner Bruno Soares also made progress as they won their first round match.
Novak Djokovic was completely untroubled as second round opponent Jiri Vesely had to pull out with an inflamed forearm, while Rafael Nadal won the first match under the new Arthur Ashe Stadium roof as he won in straight sets against Andreas Seppi.
Andy Murray will play his second round match today against Marcel Granollers, with Juan Martin del Potro also in action, as are the Williams sisters and Sam Stosur in the remaining second round matches in the women's draw.
By Keith Prowse