British number three Kyle Edmund has pulled out of the US Open with a knee injury.
Edmund, 26, underwent surgery in March for a persistent knee problem and is still not fit to return to competition.
His last match was in October last year with a qualifying first-round loss in Vienna.
The US Open begins on 28 August with Britain's Dan Evans, Cameron Norrie and former champion Andy Murray in the men's field.
Edmund's best Grand Slam performance was reaching the Australian Open semi-final in 2018, and he became the British number one, overtaking Murray in March of that year.
Since then he has slipped from a career-high world number 14 ranking to 102, with Murray likely to overtake him during the American hard court swing leading up to, and after, the US Open.
Edmund's place in the draw at Flushing Meadows will be taken by American Denis Kudla.
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