Britain's Heather Watson lost in the US Open first round for the fifth year running as she went down to American Lauren Davis in straight sets.
Davis, ranked 23 places lower at 84 in the world, won 7-6 (7-3) 7-6 (7-0) in New York.
Watson won the junior title at Flushing Meadows in 2009 but has lost all five of her first-round matches since 2011.
The five remaining Britons in the US Open singles begin their campaigns on Tuesday.
More to follow.