British number two Heather Watson could not capitalise on a lucky loser place as she lost to Australia's Daria Gavrilova at the Madrid Open.
Watson, 23, lost to Croatia's Mirjana Lucic-Baroni in qualifying on Saturday but went through as a lucky loser after illness forced out Yulia Putintseva.
However, the Briton was beaten 7-5 6-4 by Gavrilova in Sunday's first round.
Laura Robson will play Victoria Azarenka later on Sunday, while Johanna Konta faces Caroline Garcia.
Former British number one Robson is in the main draw after using her protected ranking of 58 to enter.