Maleeva was frustrated early on

Fifth seed Magdalena Maleeva slumped to a 6-7 (0-7) 6-4 6-1 defeat at the hands of Arantxa Parra in the shock of the day.

The Bulgarian looked increasingly frustrated against her 159th-ranked Spanish opponent, who was playing only her third WTA Tour main draw match of the year.

After receiving massage treatment to her back at the end of the first set, Parra always held the edge.

Her firm groundstrokes earned her a break for 1-0 in the second set and after Maleeva overhit a return on a break point to level at 3-3 the Spaniard took control.

I was a little bit lucky to win the first set Eleni Daniilidou

Sixth seed Eleni Daniilidou also struggled before overcoming Katalin Marosi 6-4 6-1.

Daniilidou took time to settle in the first set, but surrendered just two points in the first four games of the second to build up a cushion.

"It was my first match on clay this year, and in the beginning I was a little bit nervous," she said.

"It was totally different to the practice I've been doing the last three weeks.

"I was a little bit lucky to win the first set, but after 4-4 I played one game really good and it was okay after that."

Elsewhere, Austrian Barbara Schett slumped to her eighth straight first-round defeat when she was beaten 6-4 6-2 by seventh seed Anna Pistolesi .

Top seed Venus Williams can regain the number two ranking from Kim Clijsters this week.

She will play one of two qualifiers - Martina Sucha or Zuzana Ondraskova - in her opening match after receiving a first-round bye.