| Singles | |
|---|---|
| 2021 Mercer Tennis Classic | |
| Champion |  Madison Brengle |
| Runner-up |  Zarina Diyas |
| Final score | 6–4, 4–6, 6–4 |
Catherine Bellis was the defending champion [1] but chose not to participate.
Madison Brengle won the title, defeating Zarina Diyas in the final, 6–4, 4–6, 6–4.
Madison Brengle (champion) Zarina Diyas (final)
Kristína Kučová (first round, retired)
Beatriz Haddad Maia (semifinals)
Renata Zarazúa (quarterfinals, retired)
Maddison Inglis (first round)
Wang Xiyu (semifinals)
Rebecca Marino (first round)| Semifinals | Final | ||||||||||||
| 1 | Madison Brengle | 6 | 6 | ||||||||||
| 7 | Wang Xiyu | 3 | 4 | ||||||||||
| 1 | Madison Brengle | 6 | 4 | 6 | |||||||||
| 2 | Zarina Diyas | 4 | 6 | 4 | |||||||||
| 4 | Beatriz Haddad Maia | 4 | 1 | ||||||||||
| 2 | Zarina Diyas | 6 | 6 | ||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | M Brengle | 6 | 61 | 6 | |||||||||||||||||||||||
 T Andrianjafitrimo | 4 | 77 | 4 | 1 | M Brengle | 7 | 1 | 6 | |||||||||||||||||||
| G Min | 6 | 3 | 3 | Jia Lu | 5 | 6 | 2 | ||||||||||||||||||||
| Jia Lu | 1 | 6 | 6 | 1 | M Brengle | 77 | 6 | ||||||||||||||||||||
| WC | E Navarro | 6 | 6 | Q | L Chirico | 65 | 4 | ||||||||||||||||||||
| WC | H Baptiste | 2 | 4 | WC | E Navarro | 4 | 6 | 4 | |||||||||||||||||||
| Q | L Chirico | 6 | 6 | Q | L Chirico | 6 | 2 | 6 | |||||||||||||||||||
| 6 | M Inglis | 3 | 2 | 1 | M Brengle | 6 | 6 | ||||||||||||||||||||
| 3 | K Kučová | 4 | 0r | 7 | Xiy Wang | 3 | 4 | ||||||||||||||||||||
| WC | C Harrison | 6 | 0 | WC | C Harrison | 7 | 6 | ||||||||||||||||||||
 K Nara | 62 | 4 | C Dolehide | 5 | 1 | ||||||||||||||||||||||
| C Dolehide | 77 | 6 | WC | C Harrison | 4 | 6 | 65 | ||||||||||||||||||||
| L Cabrera | 7 | 6 | 7 | Xiy Wang | 6 | 3 | 77 | ||||||||||||||||||||
| WC | UM Arconada | 5 | 2 | L Cabrera | 0 | 2 | |||||||||||||||||||||
| Q | A Kiick | 0 | 0 | 7 | Xiy Wang | 6 | 6 | ||||||||||||||||||||
| 7 | Xiy Wang | 6 | 6 | ||||||||||||||||||||||||
| First round | Second round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 5 | R Zarazúa | 6 | 6 | ||||||||||||||||||||||||
 T Maria | 2 | 0 | 5 | R Zarazúa | 6 | 6 | |||||||||||||||||||||
| Q | A Smith | 6 | 5 | 6 | Q | A Smith | 4 | 3 | |||||||||||||||||||
| Q | W Osuigwe | 0 | 7 | 4 | 5 | R Zarazúa | 0r | ||||||||||||||||||||
 K Kawa | 5 | 4 | 4 | B Haddad Maia | 3 | ||||||||||||||||||||||
| Q | R Anderson | 7 | 6 | Q | R Anderson | 4 | 3 | ||||||||||||||||||||
 L Küng | 0 | 4 | 4 | B Haddad Maia | 6 | 6 | |||||||||||||||||||||
| 4 | B Haddad Maia | 6 | 6 | 4 | B Haddad Maia | 4 | 1 | ||||||||||||||||||||
| 8 | R Marino | 3 | 6 | 2 | 2 | Z Diyas | 6 | 6 | |||||||||||||||||||
| K Volynets | 6 | 2 | 6 | K Volynets | 5 | 4 | |||||||||||||||||||||
| Q | V Duval | 4 | 6 | 6 | Q | V Duval | 7 | 6 | |||||||||||||||||||
| Q | D Lao | 6 | 0 | 0 | Q | V Duval | 1 | 4 | |||||||||||||||||||
| A Muhammad | 2 | 2 | 2 | Z Diyas | 6 | 6 | |||||||||||||||||||||
| Q | H Chang | 6 | 6 | Q | H Chang | 4 | 5 | ||||||||||||||||||||
| PR | P Hon | 3 | 6 | 2 | 2 | Z Diyas | 6 | 7 | |||||||||||||||||||
| 2 | Z Diyas | 6 | 1 | 6 | |||||||||||||||||||||||
Serena Williams was the two-time defending champion, but lost in the second round to Jana Čepelová, ending her 15-match winning streak at this tournament, and her 28-match winning streak on clay.
Samantha Stosur successfully defended her title, defeating Zarina Diyas in the final, 7–6(9–7), 6–3.
Garbiñe Muguruza was the defending champion heading into the tournament but chose to compete at the Sydney tennis event instead of Hobart. In the final, it was unseeded Brit Heather Watson who defeated the American qualifier in Madison Brengle, 6–3, 6–4 to record her second WTA title.
Andrea Petkovic was the defending champion, but she lost to Angelique Kerber in the semifinals.
Monica Puig was the defending champion, but lost in the first round to Samantha Stosur.
Samantha Stosur was the defending champion, but chose not to participate.
Christina McHale was the defending champion, but lost in the semifinals to Zarina Diyas.
Caroline Wozniacki was the defending champion and successfully defended her title, defeating Anastasia Pavlyuchenkova in the final, 6–0, 7–5. This marked Wozniacki's first title of 2017 and snapped a six-match losing streak in tournament finals.
Agnieszka Radwańska was the defending champion, but lost in the third round to Daria Kasatkina.
Laura Siegemund was the defending champion, but lost in the second round to CoCo Vandeweghe.
Zarina Diyas was the defending champion, but lost in the quarterfinals to Zhang Shuai.
Sara Errani was the defending champion, but lost in the first round to Allie Kiick.
Ashleigh Barty defeated Karolína Plíšková in the final, 7–6(7–1), 6–3, to win the women's singles tennis title at the 2019 Miami Open. It marked Barty's first Miami Open title and her first WTA Premier Mandatory title. Her victory earned her a top 10 debut in the WTA rankings.
Katie Boulter was the defending champion, but chose not to participate.
Ons Jabeur was the defending champion, but chose to participate in Rosmalen instead.
Karolína Plíšková was the defending champion, but chose to participate in Korea Open, instead.
Madison Keys was the defending champion but lost in the second round to Ons Jabeur.
Johanna Konta defeated Zhang Shuai in the final, 6–2, 6–1, to win the women's singles tennis title at the 2021 Nottingham Open. The win earned Konta her fourth career singles title, her first since 2017, and made her the first British player to win a WTA Tour singles title on home soil since Sue Barker in 1981. This would also be Konta's final title before she announced her retirement in December 2021 due to a long-term knee injury.
Samantha Stosur and Zhang Shuai defeated Coco Gauff and Caty McNally in the final, 6–3, 3–6, 6–3 to win the women's doubles title at the 2021 US Open. This was Stosur's fourth major title in women's doubles and eighth major overall, as well as Zhang's second major title; this was the pair's second major title, after their victory at the 2019 Australian Open. This was the first major final that either Gauff or McNally participated in.
You Xiaodi was the defending champion but chose not to participate.