| Atlanta, USA | 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 Klein, Brydan [226] | 6-7,6-2,7-6 | |
| ATP Atlanta Qual | 07/22 16:40 | 45 | Stefan Kozlov v Gard, Catalin-Ionut | 6-3,6-1 | |
| Newport, USA | 07/17 18:45 | 25 | [140] Menendez-Maceiras, Adrian v Stefan Kozlov [129] | 6-2,7-6 | |
| Wimbledon Qual | 06/28 15:15 | 45 | [175] Novikov, Dennis 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 | |
| London, Great Britain | 06/22 11:00 | 26 | [7] Marin Cilic v Stefan Kozlov [149] | 6-0,6-4 | |
| London, Great Britain | 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] Karlovic, Ivo v Stefan Kozlov [150] | 6-4,6-1 | |
| ATP Den Bosch | 06/13 14:35 | 25 | [90] Brown, Dustin v Stefan Kozlov [150] | 3-6,6-3,3-6 | |
| Surbiton, Great Britain | 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 Stakhovsky, Sergiy [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] Kamke, Tobias v Stefan Kozlov [145] | 6-4,5-7,7-6 | |
| Challenger - Savannah | 05/05 15:00 | 27 | [342] Sorgi, Joao Pedro 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] Libietis, Mikelis 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 Melzer, Jurgen [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 Zeballos, Horacio [85] | 1-6,6-7 | |
| Challenger - Sarasota | 04/18 15:00 | 25 | [137] Stefan Kozlov v Polansky, Peter [128] | 6-4,6-4 | |
| Sarasota, USA, Qualifying | 04/17 14:00 | 54 | [137] Stefan Kozlov v Blaz Rola [264] | 6-2,4-6,2-6 | |
| Sarasota, USA, Qualifying | 04/16 18:45 | 46 | Stefan Kozlov v Geller, Axel | 6-1,6-2 | |
| Sarasota, USA, Qualifying | 04/15 19:15 | 45 | Stefan Kozlov v Chirala, Sathi Reddy | 6-0,6-0 | |
| Challenger - San Luis Potosí | 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 Ram, Rajeev [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.