Mary Pierce [Images] crushed China's Shuai Peng 6-2, 6-2 to reach the final of the Acura Classic in Carlsbad, California on Saturday.

The sixth-seeded Frenchwoman will meet Japan's [Images] Ai Sugiyama [Images] in the final after she advanced when compatriot Akiko Morigami retired with a knee injury while 4-3 down in the second set.

Sugiyama had won the first set 6-4 in a protracted baseline battle that was characterised by several long rallies.

Blasting the ball from all angles of the court, Pierce never allowed China's top-ranked player into the match, serving with weight variety, punishing her foe's second serves and keeping her groundstrokes deep.

"She's a dangerous player if you let her play, so the key the ball was hitting the ball hard and deep, staying aggressive and trying to come forward," said Pierce, who ripped 28 winners to only 13 from Peng.

"I had a couple of return games I was really happy with, staying down and hitting through the ball. In important moments I served well and that was key."

After upsetting Kim Clijsters [Images] and losing a three-set doubles contest on Friday, Peng was a step slow all day. The 19-year-old was unable to impose her baseline game and never took advantage of the opportunities given her, failing to convert on all eight of her break point opportunities, including six in the last game of the first set.

"I was really tired after playing almost four hours last night," Peng said. "My energy didn't come back. My fitness is getting better, but I need to do more."

The 30-year-old Pierce is experiencing one of the best stretches of her career, reaching the French Open [Images] final, the Wimbledon [Images] quarter-finals, winning a match at Fed Cup and now reaching her first final in San Diego since 1998.

She has won 15 of her last 17 matches.

"I feel the best I ever have," she said. "I'm playing better now than I did before. The girls are better now than before and being at the top is a lot tougher."

The double Grand Slam champion has won 14 singles titles in her 16-year career but has never won an outdoor hardcourt title in the United States, even though she learned to play in Florida [Images].

She would like to turn that around on Sunday.

"To think that there are still some firsts in my career at this stage is great," she said.

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