Emma Raducanu struggled until the midnight hour in Washington before taking a 7-6(6), 6-1 loss to Liudmila Samsonova to exit in the quarter-finals in the US capital early Saturday morning.
Raducanu worked for one and three-quarter hours to overcome her Italy-based opponent, who hammered nine aces and took advantage of seven double-fautls form the reigning US Open winner.
WTA No. 10 Raducanu lost serve five times while breaking three times.
The match stretched into the wee hours in nighttime heat and humidity typical of the city at this time of year.
Samsonova saved four Raducanu set points in the opening set before turning on her jets to run out the winner in straights and reach her second semi-final of the season after Stuttgart on indoor clay in April..
Samsonova finished with a comfortable 33 winners, while Raducanu managed just eight in her effort.
Main photo:-Liudmila Samsonova defeated Emma Raducanu – by Roger Parker International Sports Fotos Ltd