# 1998 U.S. Pro Tennis Championships – Singles

The 1998 U.S. Pro Tennis Championships was a men's tennis tournament played on Hard courts in Boston, United States that was part of the International Series of the 1998 ATP Tour. It was the seventieth edition of the tournament and was held from 24 to 30 August 1998.

## Seeds

Champion seeds are indicated in bold text while text in italics indicates the round in which those seeds were eliminated.
* Jonas Björkman (quarterfinals)
* Karol Kučera (first round)
* Cédric Pioline (semifinals)
* Michael Chang (champion)
* Thomas Muster (first round)
* Fabrice Santoro (first round)
* Andrea Gaudenzi (first round)
* Unknown (withdrew)

## Draw
### Key

* Q = Qualifier
* WC = Wild card
* LL = Lucky loser
* Alt = Alternate
* SE = Special exempt
* PR = Protected ranking
* ITF = ITF entry
* JE = Junior exempt
* w/o = Walkover
* r = Retired
* d = Defaulted
* SR = Special ranking

### Finals

| Semifinals | Semifinals | Semifinals | Semifinals | Semifinals | Final | Final | Final | Final |
| | Sébastien Grosjean | 5 | 6 | 6 | | | | |
| 4 | Michael Chang | 7 | 4 | 3 | | | | |
| 4 | Michael Chang | 7 | 4 | 3 | 4 | Michael Chang | 6 | 6 |
| | | | | | | Paul Haarhuis | 3 | 4 |
| 3 | Cédric Pioline | 5 | 6 | 3 | | Paul Haarhuis | 3 | 4 |
| | Paul Haarhuis | 7 | 4 | 6 | | | | |

### Top half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | J Björkman | 6 | 6 | | | | | | | | | | | | | | | | |
| | A Clément | 2 | 3 | | 1 | J Björkman | 6 | 7 | | | | | | | | | | | |
| | G Blanco | 3 | 6 | 6 | | G Blanco | 2 | 6$^5$ | | | | | | | | | | | |
| | H Gumy | 6 | 1 | 4 | | | | | | 1 | J Björkman | 6$^7$ | 1 | | | | | | |
| | S Grosjean | 6 | 6 | | | | | | | | S Grosjean | 7 | 6 | | | | | | |
| | J van Lottum | 2 | 0 | | | S Grosjean | 6 | 7 | | | | | | | | | | | |
| | X Malisse | 6 | 6 | | | X Malisse | 4 | 5 | | | | | | | | | | | |
| | S Campbell | 3 | 1 | | | | | | | | | | | | | S Grosjean | 5 | 6 | 6 |
| 4 | M Chang | 7 | 6 | | | | | | | | | | | | 4 | M Chang | 7 | 4 | 3 |
| | A Pavel | 5 | 2 | | 4 | M Chang | 4 | 6 | 6 | | | | | | | | | | |
| | K Carlsen | 3 | 6 | 6 | | K Carlsen | 6 | 3 | 4 | | | | | | | | | | |
| | J Golmard | 6 | 3 | 4 | | | | | | 4 | M Chang | 6 | 2 | 6 | | | | | |
| | L Roux | 6 | 6 | | | | | | | | G Pozzi | 4 | 6 | 1 | | | | | |
| | R Delgado | 4 | 2 | | | L Roux | 7 | 2 | 6$^3$ | | | | | | | | | | |
| | G Pozzi | 6 | 6 | | | G Pozzi | 5 | 6 | 7 | | | | | | | | | | |
| 6 | F Santoro | 2 | 2 | | | | | | | | | | | | | | | | |

### Bottom half

| First round | First round | First round | First round | First round | Second round | Second round | Second round | Second round | Second round | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Quarterfinals | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 5 | T Muster | 6 | 6 | | | | | | | | | | | | | | | | |
| | M Filippini | 0 | 2 | | 5 | T Muster | 6 | 6 | | | | | | | | | | | |
| | N Lapentti | 6$^8$ | 6 | 7 | | N Lapentti | 2 | 4 | | | | | | | | | | | |
| | C Costa | 7 | 4 | 5 | | | | | | 5 | T Muster | 5 | 3 | | | | | | |
| | A Ilie | 6 | 6 | | | | | | | 3 | C Pioline | 7 | 6 | | | | | | |
| | F Squillari | 4 | 2 | | | A Ilie | 4 | 2 | | | | | | | | | | | |
| 3 | C Pioline | 6 | 6 | | 3 | C Pioline | 6 | 6 | | | | | | | | | | | |
| | A Voinea | 4 | 0 | | | | | | | | | | | | 3 | C Pioline | 5 | 6 | 3 |
| | J Novák | 4 | 6 | 6 | | | | | | | | | | | | P Haarhuis | 7 | 4 | 6 |
| 7 | A Gaudenzi | 6 | 1 | 1 | | J Novák | 1 | 6 | 5 | | | | | | | | | | |
| | P Haarhuis | 6 | 6 | | | P Haarhuis | 6 | 4 | 7 | | | | | | | | | | |
| | L Arnold | 1 | 3 | | | | | | | | P Haarhuis | 0 | 6 | 6 | | | | | |
| | S Schalken | 7 | 7 | | | | | | | | S Schalken | 6 | 4 | 3 | | | | | |
| | D Sanguinetti | 6$^3$ | 6$^3$ | | | S Schalken | 6 | 6 | | | | | | | | | | | |
| | J Tarango | 6 | 6 | | | J Tarango | 1 | 1 | | | | | | | | | | | |
| 2 | K Kučera | 2 | 3 | | | | | | | | | | | | | | | | |