[67] Sam Querrey 6-7,3-6,4-6 John Isner [34] 2021-05-31 09:00
Stadium: Court 14 Round: 23 Ground: Clay
Head to Head
| ATP Acapulco | 2019/02/27 22:00 | John Isner v Sam Querrey | 6-4,6-4 |
| ATP Cincinnati | 2018/08/13 20:15 | John Isner v Sam Querrey | 4-6,7-6,6-7 |
| ATP Cincinnati | 2015/08/18 16:25 | John Isner v Sam Querrey | 3-6,6-7 |
| ATP Memphis | 2015/02/14 03:35 | John Isner v Sam Querrey | 6-7,6-7 |
Home History
| ATP Parma | 2021/05/25 13:00 | Sam Querrey v Yoshihito Nishioka | 6-3,3-6,6-7 |
| ATP Miami | 2021/03/24 16:40 | Sam Querrey v Yen-Hsun Lu | 3-6,4-6 |
| Australian Open | 2021/02/09 03:40 | Sam Querrey v Lorenzo Sonego | 5-7,4-6,4-6 |
| ATP Great Ocean Road Open | 2021/02/03 04:20 | Sam Querrey v Stefano Travaglia | 7-6,3-6,4-6 |
| ATP Great Ocean Road Open | 2021/02/02 04:05 | Sam Querrey v Henri Laaksonen | 4-6,7-6,6-0 |
| ATP Delray Beach | 2021/01/09 18:10 | Gianluca Mager v Sam Querrey | 7-6,6-1 |
| ATP Delray Beach | 2021/01/08 01:00 | Mackenzie McDonald v Sam Querrey | 3-6,4-6 |
| French Open | 2020/09/29 13:55 | Sam Querrey v Andrey Rublev | 7-6,7-6,5-7,4-6,3-6 |
Away History
| ATP Madrid | 2021/05/07 11:00 | Dominic Thiem v John Isner | 3-6,6-3,6-4 |
| ATP Madrid | 2021/05/06 13:20 | John Isner v Andrey Rublev | 7-6,3-6,7-6 |
| ATP Madrid | 2021/05/05 16:00 | Roberto Bautista-Agut v John Isner | 4-6,7-6,6-7 |
| ATP Madrid | 2021/05/03 09:00 | John Isner v Miomir Kecmanovic | 6-4,7-6 |
| ATP Miami | 2021/03/30 15:00 | John Isner v Roberto Bautista-Agut | 3-6,6-4,6-7 |
| ATP Miami | 2021/03/28 15:00 | Felix Auger Aliassime v John Isner | 6-7,6-7 |
| ATP Miami | 2021/03/27 01:05 | Mackenzie McDonald v John Isner | 6-2,3-6,5-7 |
| ATP Acapulco | 2021/03/18 04:00 | Stefanos Tsitsipas v John Isner | 6-3,6-2 |