Britain's Heather Watson was in visible discomfort as she lost in three sets to Dutch qualifier Richel Hogenkamp in the first round of the US Open.
Watson, 24, was doubled over in pain at the end of the match as she was beaten 6-2, 7-5 by the world number 165.
The British number two was in tears after losing the first set in 32 minutes and was treated by a trainer for what appeared to be a back injury.
Watson has now failed to reach the second round in six attempts.
More to follow.