Isner lost his fourth-round match to Roberto Bautista Agut in Miami on Tuesday.
| year | Event | RND | Winner | Results |
|---|---|---|---|---|
| 2021 |
Volvo Car Open
|
1/32 | Leylah Fernandez |
3-6
1-6 |
| 2021 |
Miami Open
|
1/64 | Andrea Petkovic |
7-5
6-1 |
| year | Event | RND | Winner | Results |
|---|---|---|---|---|
| 2021 |
Miami Open
|
1/64 | Yen-Hsun Lu |
3-6
4-6 |
| 2021 |
Australian Open ATP
|
1/64 | Lorenzo Sonego |
5-7
4-6 4-6 |
| 2021 |
Great Ocean Road Open
|
1/16 | Stefano Travaglia |
7-6
3-6 4-6 |
| 2021 |
Great Ocean Road Open
|
1/32 | Sam Querrey |
4-6
7-6 6-0 |
