Seven of the eight seeded players in action won their matches in the first claycourt event of the year. The only loser was No. 9 Irina Spirlea of Romania, whose slump continued.

Making her first appearance at Hilton Head since earning the title here in 1997, Hingis beat Austrian Sylvia Plischke, 6-3, 7-5, in the second round. She will meet No. 10 Conchita Martinez of Spain in the round of 16.

After losing the first three games of the second set, Hingis rebounded to win the next five games to regain control of the match.

``I kind of laid back a little bit, and right away she was there,'' Hingis said. ``She had nothing to lose, of course, as I didn't have nothing to lose at 3-0, so I just tried to be more aggressive and make more winners.''

Since falling to Venus Williams in the second round at the Sydney International in January 1998, Hingis has not lost before the quarterfinals in 24 straight events.

However, the 18-year-old Hingis has not claimed a title since defeating Amanda Coetzer in the Pan Pacific Open in Japan on February 7. It was her second consecutive triumph, having won her third straight Australian Open title the previous week. She has lost in the quarterfinals of her last three events -- the Paris Open, Evert Cup and Lipton Championships.

Martinez beat France's Alexia Dechaume-Balleret, 6-3, 6-0, in her second-round match.

Seles rolled to a 6-3, 6-0 win over Olga Barabanchikova of Belarus and will meet 14th-seeded Elena Likhovtseva of Russia in the third round.

``It's always a tough match the first time you play on clay every year,'' Seles said. ``I still have to make some adjustments, but I think by the second set I started playing a lot better.''

Seles is without a title this year but has won eight of 10 matches in Hilton Head. In addition to her final loss to Hingis, Seles reached the semifinals last season, saving five match points against Patty Schnyder in the quarterfinals.

Likhovtseva cruised to a 6-1, 6-1 win over Anne-Gaelle Sidot of France.

Schnyder, the sixth seed from Switzerland, ousted American Lisa Raymond, 6-4, 6-2. After falling behind 4-1 in the first set, Schnyder won five straight games to take control of the match.

Spirlea continued her season-long slump with a 1-6, 6-4, 6-2 loss to Iva Majoli of Croatia. She has lost seven of her last nine matches and fell to 5-7 this year. Majoli will face Schnyder.

No. 13 Silvia Farina of Italy and 16th-seeded Henrietta Nagyova of the Czech Republic also advanced to the third round. Farina beat Virginia Ruano Pascual of Spain, 7-5, 4-6, 6-3 and Nagyova downed Rita Grande of Italy, 6-1, 6-2.

Andrea Glass of Germany defeated Romania's Ruxandra Dragomir, 6-3, 6-4, in a battle of unseeded players.

Third-seeded Jana Novotna of the Czech Republic, No. 4 Arantxa Sanchez Vicario of Spain and fifth-seeded Amanda Coetzer of South Africa will play their second-round matches Thursday.

First prize is $150,000.