| Singles | |
|---|---|
| 1998 Advanta Championships of Philadelphia | |
| 1997 Champion |  Martina Hingis |
| Champion |  Steffi Graf |
| Runner-up |  Lindsay Davenport |
| Score | 4–6, 6–3, 6–4 |
Martina Hingis was the defending champion but lost in the quarterfinals to Steffi Graf.
Graf won in the final 4–6, 6–3, 6–4 against Lindsay Davenport.
A champion seed is indicated in bold text while text in italics indicates the round in which that seed was eliminated. The top four seeds received a bye to the second round.
Lindsay Davenport (final) Martina Hingis (quarterfinals)
Jana Novotná (second round)
Arantxa Sánchez-Vicario (second round) Monica Seles (semifinals)
Nathalie Tauziat (semifinals) Patty Schnyder (second round) Sandrine Testud (first round)| Final | ||||||
| 1 | Lindsay Davenport | 6 | 3 | 4 | ||
| Steffi Graf | 4 | 6 | 6 | |||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | L Davenport | 6 | 6 | ||||||||||||||||||||||||
| C Morariu | 1 | 3 | K Po | 1 | 2 | ||||||||||||||||||||||
| K Po | 6 | 6 | 1 | L Davenport | 5 | 6 | 6 | ||||||||||||||||||||
 I Majoli | 6 | 2 | 4 | Q | A Frazier | 7 | 3 | 3 | |||||||||||||||||||
| Q | A Frazier | 2 | 6 | 6 | Q | A Frazier | 6 | 6 | |||||||||||||||||||
| WC |  S Farina | 6 | 6 | 4 | 7 | P Schnyder | 3 | 1 | |||||||||||||||||||
| 7 | P Schnyder | 7 | 4 | 6 | 1 | L Davenport | 6 | 6 | |||||||||||||||||||
| 5 | M Seles | 3 | 3 | ||||||||||||||||||||||||
| 3 | J Novotná | 4 | 4 | ||||||||||||||||||||||||
 N Zvereva | 6 | 6 | N Zvereva | 6 | 6 | ||||||||||||||||||||||
| WC | T Snyder | 2 | 1 | N Zvereva | 0 | 1 | |||||||||||||||||||||
 M Vento | 1 | 2 | 5 | M Seles | 6 | 6 | |||||||||||||||||||||
 A Sugiyama | 6 | 6 | A Sugiyama | 3 | 5 | ||||||||||||||||||||||
 I Spîrlea | 3 | 4 | 5 | M Seles | 6 | 7 | |||||||||||||||||||||
| 5 | M Seles | 6 | 6 | ||||||||||||||||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 6 | N Tauziat | 6 | 6 | ||||||||||||||||||||||||
| A Huber | 3 | 2 | 6 | N Tauziat | 6 | 7 | |||||||||||||||||||||
| L Raymond | 6 | 6 | L Raymond | 2 | 6 | ||||||||||||||||||||||
| Q |  E Callens | 3 | 3 | 6 | N Tauziat | 6 | 4 | 6 | |||||||||||||||||||
| Q | S Cacic | 2 | 0 |  A Coetzer | 3 | 6 | 4 | ||||||||||||||||||||
| A Coetzer | 6 | 6 | A Coetzer | 6 | 6 | ||||||||||||||||||||||
| 4 | A Sánchez-Vicario | 4 | 1 | ||||||||||||||||||||||||
| 6 | N Tauziat | 1 | 4 | ||||||||||||||||||||||||
| 8 | S Testud | 6 | 7 | 0/r | S Graf | 6 | 6 | ||||||||||||||||||||
 E Likhovtseva | 7 | 6 | 1 | E Likhovtseva | 7 | 2 | 4 | ||||||||||||||||||||
| S Graf | 6 | 7 | S Graf | 6 | 6 | 6 | |||||||||||||||||||||
| WC | M J Fernández | 3 | 6 | S Graf | 6 | 4 | 6 | ||||||||||||||||||||
| Q | B Rippner | 7 | 6 | 2 | M Hingis | 2 | 6 | 0 | |||||||||||||||||||
| A Fusai | 6 | 2 | Q | B Rippner | 4 | 1 | |||||||||||||||||||||
| 2 | M Hingis | 6 | 6 | ||||||||||||||||||||||||
Martina Hingis defeated Monica Seles in the final, 6–2, 6–1 to win the women's singles tennis title at the 1997 Miami Open. At 16 years and 6 months, Hingis became the youngest-ever world No. 1 player in women's singles. This marked the first time that neither Steffi Graf, Seles nor Arantxa Sánchez Vicario were ranked No. 1 since August 17, 1987.
Three-time defending champion Conchita Martínez defeated Martina Hingis in the final, 6–2, 6–3 to win the women's singles tennis title at the 1996 Italian Open.
Iva Majoli was the defending champion but lost in the quarterfinals to Judith Wiesner.
Defending champion Steffi Graf successfully defended her title, defeating Martina Hingis in the final, 6–3, 4–6, 6–0, 4–6, 6–0 to win the singles tennis title at the 1996 WTA Tour Championships. It was her fifth and last Tour Finals singles title.
Martina Hingis won the singles tennis title at the 1997 Pan Pacific Open via walkover walkover after Steffi Graf withdrew from the final.
Jana Novotná and Arantxa Sánchez Vicario were the defending champions but only Novotná competed that year with Lindsay Davenport.
Martina Hingis was the defending champion and won in the final 6–0, 6–2 against Conchita Martínez.
Lindsay Davenport was the defending champion but lost in the final 5–7, 7–5, 6–4 against Monica Seles.
Jana Novotná was the defending champion but lost in the quarterfinals to Lindsay Davenport.
Jana Novotná defeated Mary Pierce in the final, 7–6, 6–3, 6–2 to win the singles tennis title at the 1997 WTA Tour Championships.
Lindsay Davenport defeated the defending champion Martina Hingis in the final, 6–3, 6–3 to win the singles tennis title at the 1998 Pan Pacific Open.
Martina Hingis defeated the defending champion Lindsay Davenport in the final, 6–3, 6–4 to win the women's singles tennis title at the 1998 Indian Wells Masters.
Martina Hingis was the defending champion but did not compete that year.
Martina Hingis was the defending champion but lost in the semifinals to Mary Pierce.
Monica Seles was the defending champion but lost in the semifinals to Lindsay Davenport.
Martina Hingis was the defending champion, but lost in the quarterfinals to Dominique Van Roost.
Martina Hingis defeated Lindsay Davenport in the final, 7–5, 6–4, 4–6, 6–2 to win the singles tennis title at the 1998 Chase Championships.
Martina Hingis defeated Amanda Coetzer in the final, 6–2, 6–1 to win the singles tennis title at the 1999 Pan Pacific Open.
Amélie Mauresmo was the defending champion but withdrew from her semifinal match against Lindsay Davenport.
Martina Hingis and Jana Novotná defeated the defending champion Natasha Zvereva and her partner Lindsay Davenport in the final, 6–1, 7–6(7–4) to win the women's doubles tennis title at the 1998 French Open. They did not drop a single set en route to the title. It was the second step in an eventual Grand Slam for Hingis.