| ATP Atlanta | 07/25 01:00 | 25 | [133] Stefan Kozlov v Quentin Halys [134] | 5-7,6-7 | |
| ATP Atlanta Qual | 07/23 15:00 | 46 | [129] Stefan Kozlov v Brydan Klein [226] | 6-7,6-2,7-6 | |
| ATP Atlanta Qual | 07/22 16:40 | 45 | Stefan Kozlov v Catalin-Ionut Gard | 6-3,6-1 | |
| ATP Newport | 07/17 18:45 | 25 | [140] Adrian Menendez-Maceiras v Stefan Kozlov [129] | 6-2,7-6 | |
| Wimbledon Qual | 06/28 15:15 | 45 | [175] Dennis Novikov v Stefan Kozlov [126] | 7-5,6-2 | |
| Wimbledon Qual | 06/26 13:15 | 44 | [200] Marc Polmans v Stefan Kozlov [126] | 4-6,5-7 | |
| ATP Queen's | 06/22 11:00 | 26 | [7] Marin Čilić v Stefan Kozlov [149] | 6-0,6-4 | |
| ATP Queen's | 06/20 11:30 | 25 | [25] Steve Johnson v Stefan Kozlov [149] | 6-3,1-6,1-6 | |
| ATP Queens Qual | 06/18 11:00 | 46 | [75] Pierre-Hugues Herbert v Stefan Kozlov [150] | 4-6,2-6 | |
| ATP Queens Qual | 06/17 11:20 | 45 | [150] Stefan Kozlov v Kenny de Schepper [148] | 6-7,6-3,6-4 | |
| ATP Den Bosch | 06/15 09:00 | 26 | [24] Ivo Karlovič v Stefan Kozlov [150] | 6-4,6-1 | |
| ATP Den Bosch | 06/13 14:35 | 25 | [90] Dustin Brown v Stefan Kozlov [150] | 3-6,6-3,3-6 | |
| Challenger Surbiton | 06/08 12:10 | 25 | [172] Akira Santillan v Stefan Kozlov [144] | 6-2,2-6,6-3 | |
| French Open Qual | 05/24 12:45 | 45 | [144] Stefan Kozlov v Sergiy Stakhovsky [122] | 7-6,4-6,4-6 | |
| French Open Qual | 05/22 14:00 | 44 | [144] Stefan Kozlov v Corentin Moutet [345] | 2-6,7-5,6-4 | |
| Challenger Heilbronn | 05/15 12:15 | 25 | [146] Tobias Kamke v Stefan Kozlov [145] | 6-4,5-7,7-6 | |
| Challenger - Savannah | 05/05 15:00 | 27 | [342] Joao Pedro Sorgi v Stefan Kozlov [144] | 6-2,6-2 | |
| Challenger - Savannah | 05/04 14:00 | 26 | [217] Ramkumar Ramanathan v Stefan Kozlov [144] | 1-6,2-6 | |
| Challenger - Savannah | 05/02 18:25 | 25 | [424] Mikelis Libietis v Stefan Kozlov [144] | 3-6,4-6 | |
| Challenger Tallahassee | 04/27 19:15 | 27 | [147] Stefan Kozlov v Mitchell Krueger [180] | 4-6,5-7 | |
| Challenger Tallahassee | 04/26 19:00 | 26 | [147] Stefan Kozlov v Jürgen Melzer [142] | 2-6,6-3,6-4 | |
| Challenger Tallahassee | 04/25 23:40 | 25 | [147] Stefan Kozlov v Federico Coria [234] | 6-3,4-6,6-4 | |
| Challenger Sarasota | 04/20 16:30 | 26 | [137] Stefan Kozlov v Horacio Zeballos [85] | 1-6,6-7 | |
| Challenger Sarasota | 04/18 15:00 | 25 | [137] Stefan Kozlov v Peter Polansky [128] | 6-4,6-4 | |
| Challenger Sarasota Qual | 04/17 14:00 | 54 | [137] Stefan Kozlov v Blaz Rola [264] | 6-2,4-6,2-6 | |
| Challenger Sarasota Qual | 04/16 18:45 | 46 | Stefan Kozlov v Axel Geller | 6-1,6-2 | |
| Challenger Sarasota Qual | 04/15 19:15 | 45 | Stefan Kozlov v Sathi Reddy Chirala | 6-0,6-0 | |
| Challenger San Luis Potosi | 04/12 01:30 | 25 | Miomir Kecmanovic v Stefan Kozlov | 6-2,7-5 | |
| Challenger Panama City | 04/03 16:30 | 25 | [120] Stefan Kozlov v Blaz Rola [282] | 1-6,6-7 | |
| Challenger - Leon | 03/30 19:00 | 26 | [122] Stefan Kozlov v Rajeev Ram [184] | 1-6,6-7 |
Wikipedia - Stefan Kozlov
Stefan Kozlov (Russian: Стефан Козлов, STEF-ahn KOZ-lov; born February 1, 1998) is an American professional tennis player of Russian descent. He has a career-high ATP ranking of world No. 103 achieved on 18 July 2022 and doubles ranking of world No. 180 on 19 June 2017.
Kozlov made his ATP World Tour debut as a wildcard in 2013 Hall of Fame Tennis Championships at the age of 15. He reached two junior Grand Slam finals in 2014 and finished the year at World No. 3 in the ITF Junior Combined rankings.