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Watson has had mixed results since then, though and - having reached a career-high ranking of 38 in January, has slipped back to 61st. The top-20 place remains some way off for the British number one.
Novak Djokovic beats Joao Souza 6-1 6-1 6-1
Venus Williams beats Monica Puig 6-4, 6-7 (7-9), 6-3
Benoit Paire knocks out last year's runner-up Kei Nishikori 6-4 3-6 4-6 7-6 (8-6) 6-4
Heather Watson loses 7-6 (7-3) 7-6 (7-0) to Lauren Davis
Watson still to win a main draw match at Flushing Meadows
Mike Whalley
Watson has had mixed results since then, though and - having reached a career-high ranking of 38 in January, has slipped back to 61st. The top-20 place remains some way off for the British number one.
3 July. Wimbledon. Centre Court. In a pulsating third-round match against Serena Williams, Heather Watson gives notice that she is ready to compete with the world's best, getting to within two points of victory before losing 6-2 4-6 7-5.
"She could get beyond the top 20, she is playing really well," Williams says afterwards.