Former Wimbledon runner-up Mark Philippoussis edged Spaniard Guillermo Garcia-Lopez 7-6, 7-6 on Thursday to reach the quarter-finals of the Ordina Open.

The Australian was nowhere near his best but snatched both sets on the tiebreak to win two consecutive matches for the first time since last year's Wimbledon.

Philippoussis now plays unseeded Italian Davide Sanguinetti, who beat Dutchman Sjeng Schalken 7-6, 6-3.

"It feels like it's been a long time since I won two (matches) in a row," Philippoussis told reporters.

"So it's all positive. I felt good out there and played well in the two tiebreaks. I just have to keep improving and keep working hard."

Wildcard Philippoussis fended off a strong challenge from Garcia-Lopez, whose ranking has climbed from 128 to 81 since the start of the year.

Philippoussis, who lost to Roger Federer [Images] in the 2003 Wimbledon final, has slipped to 188 in the rankings after a series of injuries but he has not lost the ability to play on grass, winning the first-set tiebreak 9-7 and the second 7-2.

Third seed Mario Ancic won the battle of the big-servers, the Croat beating Australian Wayne Arthurs 6-4, 7-6.

Ancic meets Jonas Bjorkman in the last eight after the Swede put out Frenchman Julien Benneteau 6-4, 6-2.

In the women's event, second seed Nadia Petrova suffered a surprise defeat, going down 6-4, 4-6, 6-3 to Argentine Gisela Dulko.

SAFINA UPSET

Sixth seed Dulko, the world number 37, reached her second semi-final of the year where she will meet unseeded Czech Lucie Safarova, who upset Russian fourth seed Dinara Safina 6-4 6-4.

Russian Petrova, a semi-finalist at the French Open earlier this month, was outplayed in the first set but varied her game well to win the second, with her old-fashioned sliced forehand keeping Dulko off balance.

But the Argentine, who reached her first tour final in Tasmania at the start of the year, broke to lead 3-1 and held her nerve to clinch victory on her third match point.

Earlier, a tearful Michaella Krajicek left the court in a wheelchair after being forced to retire from her quarter-final with a knee injury.

The 16-year-old Dutchwoman was leading American Meghann Shaughnessy 4-3 when she quit. A scan revealed she had a torn meniscus and would miss next week's Wimbledon, where she had been hoping to make her senior debut.

The teenager, half-sister of former Wimbledon champion Richard Krajicek, suffered the injury on the first point of the eighth game as she attempted a volley.

"This is the worst day of my life," she said.

Krajicek, who was also due to partner her brother in the mixed doubles at Wimbledon, said she expected to have the operation in the next week and would be out of action for at least a month.

Shaughnessy now plays Czech Klara Koukalova for a place in the final.

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