Qualifier Richel Hogenkamp has defeated Heather Watson in the opening round of the US Open.

Watson struggled throughout as the New York heat took its toll, and although she rallied during the second set, she fell to a 6-2 7-5 defeat.

The British number two experienced difficulty on her serve, and after dropping the opener she soon fell a break behind in the second as her Dutch opponent looked on course for a comfortable win.

However, Watson eventually found some rhythm during the middle stages of the second and she managed to bring up a set point, despite visibly suffering with the conditions.

Hogenkamp saved the set with an ace to wrest the momentum from Watson and she was eventually able to run out a relatively convincing winner.