Sloane Stephens is the latest American to be ousted from the second round of the 2014 U.S. Open.
She battled to take the first set against Sweden's Johanna Larsson and led 3-0 in the second set before seeming to fall apart.
"Things just got a little shaky. Obviously she played some good games after that," Stephens said after the match. "Start of the third set I tried to just put it behind me and came out swinging. I did."
Larsson took the second and third sets 6-4, 6-2. Stephens, who was the 21st seed, had 63 unforced errors in the match, which lasted more than two hours.
Stephens was not the highest-ranked player defeated on Wednesday – fourth-seeded Agnieszka Radwanska fell to China's Peng Shuai. Radwanska has notoriously struggled in Flushing Meadows, losing in the second round in five of her nine appearances here.
Still to come in the second round on Thursday, Serena WIlliams will face a fellow American for the second time in this tournament when she takes on Vania King. In the first round, Williams defeated Taylor Townsend in straight sets.
The 27th seed, Madison Keys, will play Aleksandra Krunic of Serbia; Christina McHale meets 16th seed Victoria Azarenka of Belarus while the first round's surprise star, 15-year-old CiCi Bellis, will face Zarina Diyas of Kazakhstan.
Varvara Lepchenko will face Mona Barthel of Germany; Coco Vandeweghe will face 15th seed Carla Suarez Navarro of Spain; Shelby Rogers will play 11th seed Flavia Pennetta of Italy; Nicole Gibbs takes on 23rd seed Anastasia Pavlyuchenkova of Russia (and if Gibbs and Rogers pull off the upsets, the young Americans will meet in the third round).
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