# 2021 Silicon Valley Classic – Singles

Zheng Saisai was the reigning champion but chose not to participate.
Danielle Collins won the title, her second consecutive singles title on the WTA Tour, defeating Daria Kasatkina in the final, 6–3, 6–7$^{(10–12)}$, 6–1.

## Seeds

* Elise Mertens (semifinals)
* Elena Rybakina (quarterfinals)
* Madison Keys (second round)
* Daria Kasatkina (final)
* Veronika Kudermetova (withdrew)
* Petra Martić (second round)
* Danielle Collins (champion)
* Yulia Putintseva (quarterfinals)
* Alison Riske (second round)

## 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 | Final | Final | Final | Final | Final |
| 1 | Elise Mertens | 3 | 2 | | | | | |
| 4 | Daria Kasatkina | 6 | 6 | | | | | |
| 4 | Daria Kasatkina | 6 | 6 | 4 | Daria Kasatkina | 3 | 7$^{12}$ | 1 |
| | | | | 7 | Danielle Collins | 6 | 6$^{10}$ | 6 |
| Q | Ana Konjuh | 0 | 2 | 7 | Danielle Collins | 6 | 6$^{10}$ | 6 |
| 7 | Danielle Collins | 6 | 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 |
| | | | | | 1 | E Mertens | 6 | 4 | 6 | | | | | | | | | |
| | K Mladenovic | 6 | 6 | | | K Mladenovic | 2 | 6 | 4 | | | | | | | | | |
| Q | N-l Han | 4 | 4 | | | | | | | 1 | E Mertens | 6 | 7$^{10}$ | | | | | |
| | A Tomljanović | 1 | 7 | 7 | | | | | | 8 | Y Putintseva | 3 | 6$^8$ | | | | | |
| | A Anisimova | 6 | 5 | 5 | | A Tomljanović | 6 | 5 | 3 | | | | | | | | | |
| | D Vekić | 5 | 3 | | 8 | Y Putintseva | 3 | 7 | 6 | | | | | | | | | |
| 8 | Y Putintseva | 7 | 6 | | | | | | | | | | | | 1 | E Mertens | 3 | 2 |
| | | | | | | | | | | | | | | | 4 | D Kasatkina | 6 | 6 |
| | | | | | 4 | D Kasatkina | 3 | 7 | 6 | | | | | | | | | |
| Q | E Bektas | 3 | 4 | | | C Garcia | 6 | 5 | 3 | | | | | | | | | |
| | C Garcia | 6 | 6 | | | | | | | 4 | D Kasatkina | 6 | 3 | 6 | | | | |
| | M Linette | 6 | 6 | | | | | | | | M Linette | 4 | 6 | 4 | | | | |
| Q | L Pattinama Kerkhove | 3 | 3 | | | M Linette | 7 | 7$^7$ | | | | | | | | | | |
| | A Sevastova | 3 | 3 | | 6 | P Martić | 5 | 6$^5$ | | | | | | | | | | |
| 6 | P Martić | 6 | 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 |
| 9 | A Riske | 6 | 6 | | | | | | | | | | | | | | | |
| PR | C Vandeweghe | 3 | 4 | | 9 | A Riske | 1 | 4 | | | | | | | | | | |
| | M Bouzková | 5 | 6 | 5 | Q | A Konjuh | 6 | 6 | | | | | | | | | | |
| Q | A Konjuh | 7 | 3 | 7 | | | | | | Q | A Konjuh | 3 | 6 | 6 | | | | |
| WC | E Raducanu | 3 | 2 | | | | | | | | S Zhang | 6 | 2 | 0 | | | | |
| | S Zhang | 6 | 6 | | | S Zhang | 7 | 7$^7$ | | | | | | | | | | |
| | | | | | 3 | M Keys | 5 | 6$^5$ | | | | | | | | | | |
| | | | | | | | | | | | | | | | Q | A Konjuh | 0 | 2 |
| 7 | D Collins | 6 | 6 | | | | | | | | | | | | 7 | D Collins | 6 | 6 |
| | S Rogers | 4 | 3 | | 7 | D Collins | 3 | 6 | 6 | | | | | | | | | |
| | C McNally | 4 | 2 | | | S Stephens | 6 | 4 | 3 | | | | | | | | | |
| | S Stephens | 6 | 6 | | | | | | | 7 | D Collins | 7$^7$ | 7$^7$ | | | | | |
| | D Yastremska | 3 | 6 | 4 | | | | | | 2 | E Rybakina | 6$^5$ | 6$^4$ | | | | | |
| WC | C Liu | 6 | 4 | 6 | WC | C Liu | 6 | 0 | 2 | | | | | | | | | |
| | | | | | 2 | E Rybakina | 2 | 6 | 6 | | | | | | | | | |

## Qualifying
### Seeds

* Anastasia Potapova (qualifying competition)
* Kristie Ahn (first round)
* Caty McNally (moved to main draw)
* Ana Konjuh (qualified)
* Arina Rodionova (first round)
* Lesley Pattinama Kerkhove (qualified)
* Valeria Savinykh (first round)
* Mayo Hibi (first round)

### Qualifiers

* Lesley Pattinama Kerkhove
* Han Na-lae
* Emina Bektas
* Ana Konjuh

### Qualifying draw
#### First qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 1 | Anastasia Potapova | 2 | 6 | 6 | | | | | |
| | Danielle Lao | 6 | 0 | 2 | | | | | |
| | Danielle Lao | 6 | 0 | 2 | 1 | Anastasia Potapova | 7$^7$ | 5 | 5 |
| | | | | | 6 | Lesley Pattinama Kerkhove | 6$^4$ | 7 | 7 |
| | Carol Zhao | 2 | 2 | | 6 | Lesley Pattinama Kerkhove | 6$^4$ | 7 | 7 |
| 6 | Lesley Pattinama Kerkhove | 6 | 6 | | | | | | |

#### Second qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 2 | Kristie Ahn | 3 | 6 | 0 | | | | | |
| | Han Na-lae | 6 | 2 | 6 | | | | | |
| | Han Na-lae | 6 | 2 | 6 | | Han Na-lae | 6 | 4 | 6 |
| | | | | | WC | Ashlyn Krueger | 1 | 6 | 1 |
| WC | Ashlyn Krueger | 6 | 7$^7$ | | WC | Ashlyn Krueger | 1 | 6 | 1 |
| 7 | Valeria Savinykh | 1 | 6$^2$ | | | | | | |

#### Third qualifier

| First round | First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| Alt | Emina Bektas | 6 | 1 | 6 | | | | | |
| | Katie Volynets | 4 | 6 | 3 | | | | | |
| | Katie Volynets | 4 | 6 | 3 | Alt | Emina Bektas | 6 | 5 | 6 |
| | | | | | | Ellen Perez | 4 | 7 | 4 |
| | Ellen Perez | 6 | 6$^2$ | 7 | | Ellen Perez | 4 | 7 | 4 |
| 8 | Mayo Hibi | 2 | 7$^7$ | 5 | | | | | |

#### Fourth qualifier

| First round | First round | First round | First round | Qualifying competition | Qualifying competition | Qualifying competition | Qualifying competition |
| 4 | Ana Konjuh | 6 | 6 | | | | |
| | Eri Hozumi | 3 | 2 | | | | |
| | Eri Hozumi | 3 | 2 | 4 | Ana Konjuh | 6 | 7$^7$ |
| | | | | WC | Robin Montgomery | 3 | 6$^2$ |
| WC | Robin Montgomery | 6 | 6 | WC | Robin Montgomery | 3 | 6$^2$ |
| 5 | Arina Rodionova | 4 | 0 | | | | |