Former champion Emma Raducanu is out of the US Open after losing a "rollercoaster" first-round match to Sofia Kenin.
Britain's Raducanu was searching for her first victory in New York since unexpectedly winning the title in 2021 as a teenage qualifier.
She lost in the first round the following year and missed the 2023 tournament as she recovered from wrist and ankle operations.
Raducanu's wait for another win at Flushing Meadows continues after she lost 6-1 3-6 6-4 to fellow Grand Slam champion Kenin.
Kenin, who won the Australian Open in 2020, was on the back foot early in the deciding set but it was Raducanu who faltered, dropping serve at 2-2 before Kenin saw out victory.