Anne Keothavong and Heather Watson lose in Stanford

British pair Anne Keothavong and Heather Watson have both been knocked out of the Bank of West Classic in Stanford.

Keothavong's defeat came against Mallory Burdette, who has not won a professional singles match since 2008, with the Brit falling to a 2-6 7-5 6-4 defeat.

Watson, who reached the third round at Wimbledon, fell to a 5-7 6-1 6-4 loss at the hands of world number 37 Yanina Wickmayer.

Both players had hoped to gain some competitive match practice before they represent Team GB at the Olympics.