CARLSBAD. Calif. Aug 7: Steffi Graf played toughest on crucial points to defeat seventh-seeded Mary Pier-

ce 6 3. 6-4 Friday and advance to the semifinals of the Mazda Classic, reports AP.

Pierce, an 18-year-old facing Graf for the first time, had powerful shots to challenge Graf but couldn't match her consistency. Although she had nine beak points. Pierce converted only once.

When It was Important. I played very well," Graf sald.T'm happy I won those break points. But I would have liked to win more points when it was 30-0 or so."

Graf will play Saturday in the dlrs 375.000 event against third seeded Conchita Martinez, who advanced with a 6-3, 6-2 victory over No. 5 Magdalena Maleeva It will be a rematch of their Wimbledon semifinal, won by Graft 7-6 (7-0), 6-3 on her

way to the championship.

Second-seeded Aranxta Sanchez-Vicario defeated No. 11 Ann Grossman 6-0. 6-0 and will play Germany’s Marketa Ko-chta. who defeated Yelena Llkhovtseva 6-1, 6-2. Kochta is the first qualifier to reach the semifinals In the 10-year history of the event.

Grossman and Sanchez-Vicario dueled from the baseline with long rallies. In the second set. a frustrated Grossman yelled, "When are you going to miss it?"

"I heard her that one time, but mostly. I was concentrating on every shot/ said Sanchez-Vicario. "1 hit the ball strong. She could get frustrated because she didn't have many chances."

Sanchez-Vicario made only 12 unforced errors and won 50 of 71 points.

Pterce. ranked 14th in the world, took a 3-2 lead with her only successful break in the Second set. She benefited when

the chair umpire overruled on a Graf forehand that was called long.

1 was very, very upset by that call. Everyone around there agreed it was out." Graf said. "Still, It was my mistake not to concentrate on the next few points."

Pterce called for a trainer to retape her strained right leg during the following break, and although she later said there was no pain, she lost the next three games

1 have mixed feeling about today's match," Pierce said. "It was great to play the No. 1 player and I had some great shots. But 1 need to improve on the big points. It's disappointing to come close and end up losing."

This waa Pierce's first tournament since dropping her controversial father as her coach two weeks ago. Jim Pierce has been banned from tour events for two years because of disruptive behaviour.