MANHATTAN BEACH, Calif. (AP) -- Martina Hingis couldn't believe how easy the first set was against qualifier Lisa Raymond.

Hingis won 6-1 in 28 minutes and appeared to be on her way to another victory.

``I was kind of surprised I did so well in the first set,'' the No. 2 seed said. ``But I didn't miss much. When I had the opportunity to do something, she would just miss.''

But a determined Raymond started getting her groundstrokes deep, including her one-handed slice backhand, and served harder.

She broke Hingis to start the second set when the Swiss teen-ager netted a backhand. Another backhand error by Hingis put Raymond ahead 3-1.

Raymond led 5-4 when she fought off two break points, got to deuce, then hit consecutive forehand volley winners to win the set.

The players traded breaks to open the final set as the crowd grew louder in its support of Raymond, who is ranked 29th in the world and has one career victory over Hingis in five meetings.

``She knows I certainly have the game to beat her,'' Raymond said. ``She was getting pretty fussy there in the second and third. I really felt like I could win.''

With Hingis ahead 4-3, Raymond again had two break points against her, only to get to deuce with a backhand volley winner. She twice held the advantage, but netted a backhand for the third deuce.

Hingis pounced with a backhand passing shot for her third break point. Raymond missed her first serve, then drilled a forehand into the net to trail 5-3.

``Martina's experienced enough that she knows when she's down an ad, she's going to go for it. And she did, she hit a great return at my feet,'' Raymond said.

Hingis easily served out the match, hitting an ace on match point.

``It's very tough playing her,'' she said. ``She slices that backhand very deep. She's very aggressive. You have to work for your points. She doesn't give anything for free.''

No. 3 Mary Pierce defeated Ai Sugiyama 6-3, 7-5 a week after being upset by the Japanese player in the first round of the TIG Classic at Carlsbad.

``You don't want to think about it too much, but you don't ever forget it,'' Pierce said. ``Going out today, I was trying to think about matches when I had beaten her and what I did last week, why I lost and try to not do that again.''

Pierce twice broke Sugiyama's serve in the first set, occasionally venturing to the net for volleys or drop-shotting her.

``To beat her you have to really be on your game and playing well and not making unforced errors,'' Pierce said.

In other matches, fourth-seeded Aranxta Sanchez-Vicario defeated Ruxandra Dragomir of Romania 6-3, 6-1; No. 6 Serena Williams beat Patty Schnyder of Switzerland 6-3, 6-1; and Julie Halard-Decugis of France got by Amy Frazier 7-6 (7-5), 7-5.

Williams advanced to a quarterfinal tonight against Sanchez-Vicario, who holds a 4-0 career edge.

``Be really consistent and attack her balls and expect her to get everything back,'' Williams said of her game plan. ``She has a lot more titles than I do, she's a great player, so just make sure I'm focused.

``I don't like people to hit winners on me. I don't like to see a ball go past me. That makes me feel hurt,'' she said.