| Challenger Astana | 07/23 08:20 | 14 | Arslanbek Aitkulov v Denis Istomin | 6-2,6-4 | |
| Challenger Roma | 04/24 09:10 | 19 | [435] Denis Istomin v Francesco Forti [357] | 1-6,3-6 | |
| Challenger Roma | 04/23 08:00 | 14 | Sebastian Fanselow v Denis Istomin | 4-6,6-4,3-6 | |
| Challenger Maia | 11/29 14:55 | 25 | [93] Nuno Borges v Denis Istomin [481] | 6-3,6-0 | |
| Challenger Maia | 11/28 13:20 | 19 | [293] Denis Yevseyev v Denis Istomin [481] | 3-6,3-6 | |
| Challenger Maia | 11/27 14:05 | 14 | Guilherme Valdoleiros v Denis Istomin | 1-6,1-6 | |
| Challenger Andria | 11/20 15:10 | 14 | [478] Denis Istomin v David Poljak [442] | 2-6,3-6 | |
| Challenger Bratislava | 11/06 13:10 | 14 | [447] Denis Istomin v Cem Ilkel [318] | 6-7,5-7 | |
| Challenger Ortisei | 10/23 08:00 | 14 | [445] Denis Istomin v Andrew Paulson [374] | 4-6,4-6 | |
| ATP Nur-Sultan | 10/01 08:30 | 14 | [72] Laslo Djere v Denis Istomin [424] | 6-1,6-4 | |
| Coppa Davis | 09/17 14:40 | 5 | Denis Istomin v Shintaro Mochizuki | Cancelled | |
| Coppa Davis | 09/16 06:00 | 1 | [420] Denis Istomin v Sho Shimabukuro [353] | 6-3,6-7,6-7 | |
| Challenger Nonthaburi | 09/09 03:00 | 26 | [435] Denis Istomin v Omar Jasika [367] | 4-6,3-6 | |
| Challenger Nonthaburi | 09/06 05:30 | 25 | [326] Dane Sweeny v Denis Istomin [435] | 2-6,3-6 | |
| Challenger Nonthaburi - Qual. | 08/28 09:20 | 14 | [499] Timo Legout v Denis Istomin [430] | 6-4,6-4 | |
| Challenger Nonthaburi | 08/21 06:00 | 14 | [428] Denis Istomin v Dayne Kelly [479] | 3-6,0-6 | |
| Challenger - Segovia | 07/26 11:10 | 25 | [345] Alibek Kachmazov v Denis Istomin [438] | 0-6,6-4,7-6 | |
| Challenger - Segovia | 07/25 13:10 | 19 | [386] Elmar Ejupovic v Denis Istomin [438] | 6-2,6-7,4-6 | |
| Challenger - Segovia | 07/24 16:15 | 14 | [499] Wilson Leite v Denis Istomin [449] | 7-5,5-7,5-7 | |
| Challenger Nur-Sultan | 07/22 07:10 | 27 | [449] Denis Istomin v Beibit Zhukayev [375] | 7-6,6-7,6-7 | |
| Challenger Nur-Sultan | 07/20 07:05 | 26 | [288] Illya Marchenko v Denis Istomin [449] | 4-6,6-7 | |
| Challenger Nur-Sultan | 07/19 05:45 | 25 | [441] Yan Bondarevskiy v Denis Istomin [449] | 3-6,6-3,2-6 | |
| Challenger Porto | 07/03 17:05 | 14 | Thomaz Bellucci v Denis Istomin | 6-1,6-3 | |
| Challenger Malaga | 06/26 14:45 | 14 | Denis Istomin v Alejandro T Alvarez | 6-1,6-7,3-6 | |
| Challenger Shymkent | 05/17 05:55 | 25 | [318] Sebastian Fanselow v Denis Istomin [303] | 6-1,6-4 | |
| Challenger Shymkent | 05/10 11:55 | 25 | [495] Evan Zhu v Denis Istomin [299] | 6-1,3-6,6-1 | |
| Challenger Morelos | 04/25 21:35 | 25 | [141] Ernesto Escobedo v Denis Istomin [283] | 6-4,6-4 | |
| Challenger Aguascalientes | 04/21 16:00 | 26 | [185] Federico Gaio v Denis Istomin [286] | 6-4,6-2 | |
| Challenger Aguascalientes | 04/19 20:30 | 25 | [310] Antoine Bellier v Denis Istomin [286] | 6-7,7-5,3-6 | |
| Challenger San Luis Potosi | 04/13 21:45 | 26 | [296] Denis Istomin v Ernesto Escobedo [143] | 4-6,6-4,3-6 |
Wikipedia - Denis Istomin
Denis Istomin (Orenburg, 7 settembre 1986) è un ex tennista e allenatore di tennis uzbeko di origini russe.