# 1990 Virginia Slims of Oklahoma – Singles

Manon Bollegraf was the defending champion, but lost in the final to 17-year-old Amy Frazier. The score was 6–4, 6–2.

## Seeds

* Manuela Maleeva-Fragnière (semifinals)
* Raffaella Reggi (second round)
* Amy Frazier (champion)
* Catarina Lindqvist (second round)
* Manon Bollegraf (final)
* Anne Minter (quarterfinals)
* Betsy Nagelsen (first round)
* Etsuko Inoue (quarterfinals)

## 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 |
| 1 | Manuela Maleeva-Fragnière | 6 | 3 | 3 | | | | |
| 3 | Amy Frazier | 1 | 6 | 6 | | | | |
| 3 | Amy Frazier | 1 | 6 | 6 | 3 | Amy Frazier | 6 | 6 |
| | | | | | 5 | Manon Bollegraf | 4 | 2 |
| 5 | Manon Bollegraf | 6 | 7 | | 5 | Manon Bollegraf | 4 | 2 |
| | Angélica Gavaldón | 4 | 5 | | | | | |

### 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 | Semifinals | Semifinals | Semifinals | Semifinals | Semifinals |
| 1 | M Maleeva-Fragnière | 6 | 6 | | | | | | | | | | | | | | | |
| Q | S Smith | 2 | 1 | | 1 | M Maleeva-Fragnière | 6 | 6 | | | | | | | | | | |
| | K Jordan | 7 | 6 | 6 | | K Jordan | 1 | 2 | | | | | | | | | | |
| | H Na | 6 | 7 | 3 | | | | | | 1 | M Maleeva-Fragnière | 6 | 6 | | | | | |
| | R White | 7 | 7 | | | | | | | 8 | E Inoue | 2 | 0 | | | | | |
| | T Whitlinger | 6 | 6 | | | R White | 6 | 1 | | | | | | | | | | |
| | M Javer | 2 | 3 | | 8 | E Inoue | 7 | 6 | | | | | | | | | | |
| 8 | E Inoue | 6 | 6 | | | | | | | | | | | 1 | M Maleeva-Fragnière | 6 | 3 | 3 |
| 3 | A Frazier | 6 | 1 | 7 | | | | | | | | | | 3 | A Frazier | 1 | 6 | 6 |
| Q | P Hy | 3 | 6 | 6 | 3 | A Frazier | 6 | 6 | | | | | | | | | | |
| | N Miyagi | 6 | 7 | | | N Miyagi | 2 | 0 | | | | | | | | | | |
| | Ca MacGregor | 2 | 5 | | | | | | | 3 | A Frazier | 6 | 7 | | | | | |
| | W White | 3 | 4 | | | | | | | 6 | A Minter | 2 | 6 | | | | | |
| | ML Daniels | 6 | 6 | | | ML Daniels | 1 | 6 | 0 | | | | | | | | | |
| | M Werdel | 6 | 6 | 3 | 6 | A Minter | 6 | 3 | 6 | | | | | | | | | |
| 6 | A Minter | 7 | 4 | 6 | | | | | | | | | | | | | | |

### 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 |
| 5 | M Bollegraf | 6 | 6 | | | | | | | | | | | | | | | |
| | A Coetzer | 1 | 3 | | 5 | M Bollegraf | 6 | 6 | | | | | | | | | | |
| | C Cunningham | 6 | 6 | | | C Cunningham | 4 | 2 | | | | | | | | | | |
| Q | P Vásquez | 2 | 4 | | | | | | | 5 | M Bollegraf | 6 | 6 | | | | | |
| | R Simpson | 6 | 0 | 1 | | | | | | Q | J Santrock | 4 | 2 | | | | | |
| Q | J Santrock | 3 | 6 | 6 | Q | J Santrock | 1 | 6 | 6 | | | | | | | | | |
| | C Benjamin | 2 | 2 | | 4 | C Lindqvist | 6 | 1 | 4 | | | | | | | | | |
| 4 | C Lindqvist | 6 | 6 | | | | | | | | | | | | 5 | M Bollegraf | 6 | 7 |
| 7 | B Nagelsen | 3 | 6 | | | | | | | | | | | | | A Gavaldón | 4 | 5 |
| | A Gavaldón | 6 | 7 | | | A Gavaldón | 6 | 6 | | | | | | | | | | |
| | P Louie Harper | 6 | 6 | | | P Louie Harper | 1 | 4 | | | | | | | | | | |
| | M Norwood | 0 | 2 | | | | | | | | A Gavaldón | 3 | 6 | 7 | | | | |
| | L Allen | 1 | 4 | | | | | | | | B Schultz | 6 | 4 | 5 | | | | |
| | B Schultz | 6 | 6 | | | B Schultz | 7 | 6 | | | | | | | | | | |
| | M Strandlund | 3 | 3 | | 2 | R Reggi | 5 | 2 | | | | | | | | | | |
| 2 | R Reggi | 6 | 6 | | | | | | | | | | | | | | | |