ROME (Reuters):

Former world number one Serena Williams slid out of the Italian Open following a 6-3, 2-6, 7-6 defeat by Patty Schnyder in the quarter-finals yesterday.

Playing her first tournament since a groin strain forced her to pull out of the Family Circle Cup in Charleston last month, Williams struggled to find her rhythm against the 14th seed and paid the price for an error-strewn performance.

"I'm just really surprised that I won. In the first set she was missing a lot, then in the second my game went wrong," said Schnyder. "The third set was just really tough, very close. I tried to mix it up, but she's such a champion that you have to expect her to hit a lot of winners. I'm really happy and lucky to be through to the next round."

Schnyder's reward will be a semi-final against third seed Jelena Jankovic, who produced an impressive display of baseline hitting to sweep past Elena Dementieva 6-2, 6-1.

In the other half of the draw, second seed Svetlana Kuznetsova also progressed with a 6-1 6-3 win over fellow Russian Dinara Safina to set up a last four meeting with ninth seed Daniela Hantuchova, who knocked out Anabel Medina Garrigues 7-6 , 7-5.

Williams, the Australian Open champion, was left to reflect on a wayward performance.

"I just didn't make the shots that I should have. I probably hit about 50 unforced errors, which is pretty good to get to 7-6 in the third (set)," she said.

Asked whether she still felt confident of a good run at Roland Garros later this month, the American replied: "Absolutely. It's good to get some hard matches and long points under my belt."