British number one Johanna Konta has pulled out of her second-round match with Carla Suarez Navarro at the Connecticut Open due to a viral illness.
The 27-year beat Germany's Laura Siegemund in the first round at New Haven and was due to take on Spaniard Navarro on Tuesday.
However, Konta has now been forced to withdraw from both the singles event and the doubles, where she was competing with American partner Nicole Melichar.
The tournament is the final warm-up event before the US Open, which gets underway at Flushing Meadows on August 27.
Konta - ranked 46th in the world - is the only British woman with direct entry into the main draw of the US Open, although she will be unseeded at the final Grand Slam of the year.