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)

ResultW–LDateTournamentTierSurfaceOpponentScore
Loss0–12014 Sacramento Challenger – Singles|Sacramento, USChallengerHard Sam Querrey3–6, 4–6
Loss0–2USA F15, Orange ParkFuturesHard Darian King2–6, 6–3, 0–6
Loss0–3Mexico F3, Mexico CityFuturesHard Iván Endara1–6, 6–7
Loss0–4Belarus F3, MinskFuturesHard Dzmitry Zhyrmont1–6, 4–6
Win1–4Belarus F4, MinskFuturesHard Dzmitry Zhyrmont6–1, 7–6
Win2–4USA F1, Los AngelesFuturesHard Philip Bester7–6, 6–7, 6–3
Win3–4Canada F2, SherbrookeFuturesHard Lloyd Glasspool4–6, 6–4, 6–4
Loss3–52016 Open de Guadeloupe – Singles|Le Gosier, GuadeloupeChallengerHard Malek Jaziri2–6, 4–6
Win4–5USA F13, Little RockFuturesHard Eric Quigley6–7, 6–3, 7–6
Loss4–62016 China International Suzhou – Singles|Suzhou, ChinaChallengerHard Lu Yen-hsun0–6, 1–6
Win5–62016 Columbus Challenger 2 – Singles|Columbus, USChallengerHard Tennys Sandgren6–1, 2–6, 6–2
Win6–62017 Las Vegas Challenger – Singles|Las Vegas, USChallengerHard Liam Broady3–6, 7–5, 6–4

Doubles: 9 (4–5)

ResultW–LDateTournamentTierSurfacePartnerOpponentsScore
Win1–0USA F31, BradentonFuturesClay Sekou Bangoura Devin McCarthy
Tommy Mylnikov
6–2, 6–4
Loss1–1Spain F10, VicFuturesClay Noah Rubin Sergio Martos Gornés
Pol Toledo Bagué
2–6, 5–7
Win2–12015 Royal Lahaina Challenger – Doubles|Maui, USChallengerHard Jared Donaldson Chase Buchanan
Rhyne Williams
6–3, 6–4
Loss2–2Croatia F18, SolinFuturesClay Nino Serdarušić Zdeněk Kolář
Tomas Toman
4–6, 6–2,
Win3–2Canada F1, GatineauFuturesHard Kaichi Uchida Sebastian Fanselow
Adrian Sikora
7–6, 6–3
Win4–22016 Nielsen Pro Tennis Championships – Doubles|Winnetka, USChallengerHard John-Patrick Smith Sekou Bangoura
David O'Hare
6–3, 6–3
Loss4–32016 Cary Challenger – Doubles|Cary, USChallengerHard Austin Krajicek Philip Bester
Peter Polansky
2–6, 2–6
Loss4–42016 Ningbo Challenger – Doubles|Ningbo, ChinaChallengerHard Akira Santillan Jonathan Eysseric
Sergiy Stakhovsky
4–6, 6–7
Loss4–52017 Sarasota Open – Doubles|Sarasota, USChallengerClay Peter Polansky Scott Lipsky
Jürgen Melzer
2–6, 4–6

Junior Grand Slam finals

Boys' Singles

Boys' Doubles