HILTON HEAD ISLAND, S.C. (AP) -- When Martina Hingis won the Family Circle Cup two years ago, she was on another level. Now, her dominance is not so clear cut.

``Everybody has improved so much,'' said Hingis, the tournament's top seed who dispatched Sylvia Plischke 6-3, 7-5 in her first match Wednesday. ``The Williams sisters, Lindsay (Davenport) took overNo. 1 for a while. There are so many more dangerous players to watch out for.''

But many of them have decided to pass on the event.

Hingis seems to have the inside track to the tournament title with Serena Williams and Davenport out with injuries, and Venus Williams' decision to skip the Family Circle.

However, second-seeded Monica Seles, No. 6 Patty Schnyder and No. 10 Conchita Martinez may challenge Hingis. They advanced, as did No. 13 Silvia Farina, No. 14 Elena Likhovtseva and No. 16 Henrieta Nagyova.

Hingis rose to No. 1 at this tournament in 1997 and, when it was over, had extended her streak to 31 straight match victories and six straight championships.

She was 16 years old, won three of the four Grand Slams that year and finished with a tour-best 75 match wins.

Last year, Hingis learned it wasn't easy to stay on top. She won five times, down from her 12 titles a year earlier, and took only one major, the Australian Open.

By year's end, Davenport supplanted Hingis as No. 1 and sisters Venus and Serena Williams began to crowd the spotlight Hingis had owned.

``I know how I felt when I kind of played at the top level and nobody was beating me. You just feel invincible,'' Hingis said.

Especially one who's back on top after regaining No. 1 with consecutive wins at the Australian and Pan Pacific tournaments in February.

After taking the first set against Plischke without much trouble, Hingis fell behind in the second 3-0. Just as suddenly, she was up 5-3. Yet, she needed four more games to close out Plischke.

``I had kind of relaxed after the first set,'' she said. ``I just should have gone for it more.''

Seles looked sharp in her opening match, winning the final eight games to beat Olga Barabanschiova 6-3, 6-0.

Schnyder defeated Lisa Raymond 6-4, 6-2 while Martinez, who won this tournament in 1994-95, ousted Alexia Dechaume-Balleret 6-3, 6-0.