Britain's Johanna Konta reached the US Open third round - despite collapsing on court with blurred vision and breathing issues.
The 13th seed led Bulgaria's Tsvetana Pironkova 6-2 5-6 at Flushing Meadows when she crouched down to her knees and appeared to be hyper-ventilating.
Medical help arrived after several minutes, with Konta describing blurred vision and an increased heart rate.
The Briton, 25, took a lengthy break but recovered to win 6-2 5-7 6-2.
Konta followed compatriot Kyle Edmund on to court 13, with the Yorkshireman also through to the third round after a 7-5 6-4 6-4 win over American wild card Ernesto Escobedo.