Stefan Kozlov
Stefan Kozlov is an American professional tennis player of Russian descent. He is the son of Russian parents and his father is a tennis coach.
Kozlov made his ATP World Tour debut as a wild card in Newport at the age of 15. He reached two junior Grand Slam finals in 2014 and finished the year at No. 3 in the ITF Junior Combined rankings.
Junior career
In 2014, Kozlov reached two junior grand slam finals, where he lost to Alexander Zverev at the Australian Open and Noah Rubin at Wimbledon. This success led him to a career high junior ranking of No. 2. Kozlov also competed at the U18 National Championships, finishing in third place in the singles tournament and winning the doubles tournament with Noah Rubin. With this victory, they earned a wild card into the main draw of the 2014 US Open. He ended the year by winning the Orange Bowl junior tournament.In 2015, Kozlov reached the final of the U18 National Championships, where he lost to Frances Tiafoe in five sets.
Professional career
Early years
Kozlov made his ATP World Tour debut as a wild card at the Newport tournament in 2013 and lost in the first round. At the age of 16, he defeated his first Top 100 player in Tim Smyczek to reach his first ATP Challenger final in Sacramento, where he lost to Sam Querrey. He has also reached seven career ITF Futures finals and won four of these finals.2016: First ATP win and Challenger title
In April, Kozlov reached the final at the Open de Guadeloupe. In June, he won his first career ATP level match as a wild card at the Rosmalen Grass Court Championships in Den Bosch. Toward the end of the season, Kozlov reached a second Challenger final on the year at Suzhou. He won his first career Challenger event at Columbus.Challenger and Futures finals
Singles: 12 (6–6)
Result | W–L | Date | Tournament | Tier | Surface | Opponent | Score |
Loss | 0–1 | 2014 Sacramento Challenger – Singles| | Sacramento, US | Challenger | Hard | ![]() | 3–6, 4–6 |
Loss | 0–2 | USA F15, Orange Park | Futures | Hard | ![]() | 2–6, 6–3, 0–6 | |
Loss | 0–3 | Mexico F3, Mexico City | Futures | Hard | ![]() | 1–6, 6–7 | |
Loss | 0–4 | Belarus F3, Minsk | Futures | Hard | ![]() | 1–6, 4–6 | |
Win | 1–4 | Belarus F4, Minsk | Futures | Hard | ![]() | 6–1, 7–6 | |
Win | 2–4 | USA F1, Los Angeles | Futures | Hard | ![]() | 7–6, 6–7, 6–3 | |
Win | 3–4 | Canada F2, Sherbrooke | Futures | Hard | ![]() | 4–6, 6–4, 6–4 | |
Loss | 3–5 | 2016 Open de Guadeloupe – Singles| | Le Gosier, Guadeloupe | Challenger | Hard | ![]() | 2–6, 4–6 |
Win | 4–5 | USA F13, Little Rock | Futures | Hard | ![]() | 6–7, 6–3, 7–6 | |
Loss | 4–6 | 2016 China International Suzhou – Singles| | Suzhou, China | Challenger | Hard | ![]() | 0–6, 1–6 |
Win | 5–6 | 2016 Columbus Challenger 2 – Singles| | Columbus, US | Challenger | Hard | ![]() | 6–1, 2–6, 6–2 |
Win | 6–6 | 2017 Las Vegas Challenger – Singles| | Las Vegas, US | Challenger | Hard | ![]() | 3–6, 7–5, 6–4 |
Doubles: 9 (4–5)
Result | W–L | Date | Tournament | Tier | Surface | Partner | Opponents | Score |
Win | 1–0 | USA F31, Bradenton | Futures | Clay | ![]() | ![]() ![]() | 6–2, 6–4 | |
Loss | 1–1 | Spain F10, Vic | Futures | Clay | ![]() | ![]() ![]() | 2–6, 5–7 | |
Win | 2–1 | 2015 Royal Lahaina Challenger – Doubles| | Maui, US | Challenger | Hard | ![]() | ![]() ![]() | 6–3, 6–4 |
Loss | 2–2 | Croatia F18, Solin | Futures | Clay | ![]() | ![]() ![]() | 4–6, 6–2, | |
Win | 3–2 | Canada F1, Gatineau | Futures | Hard | ![]() | ![]() ![]() | 7–6, 6–3 | |
Win | 4–2 | 2016 Nielsen Pro Tennis Championships – Doubles| | Winnetka, US | Challenger | Hard | ![]() | ![]() ![]() | 6–3, 6–3 |
Loss | 4–3 | 2016 Cary Challenger – Doubles| | Cary, US | Challenger | Hard | ![]() | ![]() ![]() | 2–6, 2–6 |
Loss | 4–4 | 2016 Ningbo Challenger – Doubles| | Ningbo, China | Challenger | Hard | ![]() | ![]() ![]() | 4–6, 6–7 |
Loss | 4–5 | 2017 Sarasota Open – Doubles| | Sarasota, US | Challenger | Clay | ![]() | ![]() ![]() | 2–6, 4–6 |