Heather Watson
Heather Watson is yet to progress beyond the first round at the US OpenGetty

Great Britain's Heather Watson has fallen in the first round at the US Open for the fifth time in her career to date following a straight-sets defeat to lower-ranked American Lauren Davis.

The world number 61, who progressed through to the third round at Wimbledon last month and came agonisingly close to victory over Serena Williams, won the junior title at Flushing Meadows in 2009 but her wait for a first senior singles victory at the competition will go on for at least another year after she was beaten 7-6, 7-6 in a time of two hours and eight minutes out on court 17.

After breaking serve in the ninth game, Davis relinquished her advantage soon after but remained composed to take the tiebreak 7-3 in dominant fashion. She broke for a second time in the fourth game of the second set after three unforced errors from Watson, but again failed to hold the lead and was pegged back immediately.

The pair traded breaks once again to lead to another decider and once again Davis was very impressive as she secured the win without dropping a single point. The 21-year-old will now face 13th seed Ekaterina Makarova in round two after she came through her match against Brazilian Teliana Pereira 6-3, 6-3.

In the men's draw, 2014 finalist Kei Nishikori was a notable early casualty as he lost in five sets to Benoit Paire. Andy Murray begins his quest for a second US Open title against controversial Australian right-hander Nick Kyrgios on 1 September.