On the men's side, 15th seed and former No. 1 Patrick Rafter continues his comeback from shoulder surgery tonight with a second-round matchup against Max Mirnyi of Belarus. Rafter's fellow Australian, 14th seed Lleyton Hewitt, plays Gaston Gaudio of Argentina this afternoon.

Hingis has held the No. 1 ranking since August 9 but Lindsay Davenport's extraordinary 19-1 run has pulled the second-seeded American to within 191 points of the top spot. Whoever advances further at this event most likely will hold No. 1 when the new rankings are released.

A winner here in 1997, Hingis is 20-3 this season, winning the Pan Pacific Open in February. She lost to Davenport in the finals of the Australian Open in January and last week's Tennis Masters Series event at Indian Wells, California. The two were to have squared off for the State Farm Tennis Classic title at Scottsdale, Arizona earlier this month but the match was rained out.

Fourth seed Nathalie Tauziat of France, who has lost two of her last three matches since winning the Open Gaz de France in February, encounters American Tara Snyder, and sixth seed Conchita Martinez of Spain, a quarterfinalist last week in California, goes against Australian teenager Jelena Dokic.

Seventh seed Monica Seles of the United States plays countrywoman Lilia Osterloh today in the second round. Seles, a two-time champion here, has reached consecutive quarterfinals since winning the first tournament in which she played, the IGA Superthrift Tennis Classic, in February.

Ninth seed Anna Kournikova of Russia, the 1998 runner-up, takes on American Jennifer Hopkins tonight. The 18-year-old Miami resident has reached three semifinals this season but is hoping to bounce back from a third-round setback last week in Indian Wells.

Hopkins, who received a wild-card entry, is ranked 124th in the world. The 19-year-old registered breakthrough results last year on the USTA Satellite and Challenger Circuit, winning in Springfield, Missouri; Hilton Head, South Carolina; Little Rock, Arkansas; and Albuquerque, New Mexico.

Also, No. 11 Barbara Schett of Austria plays Adriana Gersi of the Czech Republic, No. 14 Anke Huber of Germany battles Tatiana Poutchek of Belarus, and 16th-seeded Dominique Van Roost of Belgium faces Holly Parkinson of the United States.

Eight other women's seeds also are in action. There are 32 seeds in the event.

Rafter is recovering from a injury to the rotator cuff in his right shoulder that kept him out of competition for nearly six months. After briefly playing doubles in January at Sydney, the 27-year-old made a successful singles return on February 29 in Delray Beach, Florida, where he reached the quarterfinals.

However, he lost in the first round the next week in Scottsdale and was a second-round loser last week at Indian Wells, losing to eventual champion Alex Corretja of Spain in three sets.

Rafter, a semifinalist in this event in 1994, fell in the third round here last year.

Hewitt, 19, is 21-2 this season and leads the ATP Tour with three titles -- two in his homeland and one in Scottsdale. He lost in the second round last week at Indian Wells.

In night matchs, No. 18 Sebastien Grosjean of France, last year's runner-up, meets Sjeng Schalken of the Netherlands, and 19th seed Tommy Haas of Germany squares off against 17-year-old Florida native Mardy Fish, who was leading Galo Blanco, 6-4, 0-6, 4-1, Thursday when the Spaniard retired with an injury.

Earlier, No. 16 Younes El Aynaoui of Morocco plays Byron Black of Zimbabwe and 17th-seeded Greg Rusedski of Britain faces Ukraine's Andrei Medvedev, last year's French Open finalist.

Sixteen first-round matches also are on today's slate, including American Jim Courier's encounter with David Nalbandian of Argentina. Courier, a Florida native, has been playing at this event since 1988 and won the championship in 1991.

First prize for the men's champion is $410,000, while the women's winner pockets $350,000.