British number two Heather Watson was knocked out the Citi Open in the first round with a straight-set defeat by Romania’s Patricia Maria Tig.
The 25-year-old lost 7-6 (7-4) 7-6 (7-3) in two hours three minutes to the world number 134 in Washington.
Watson, who wasted set points of her own in the first set, saved two match points before Tig took the tie-break to win her first match since March.
Tig will face Monica Niculescu or Nao Hibino in round two.
Watson had progressed through two rounds of qualifying to reach the opening round on Tuesday.
Britain’s Jamie Murray and Brazilian doubles partner Bruno Soares were at 6-6 in the first set against France’s Edouard Roger-Vasselin and American Steve Johnson when their match was delayed because of rain.
British number two Kyle Edmund is also due on court to face South Korea’s Chung Hyeon.