Stefan Kozlov

For other uses, see Kozlov.

Stefan Kozlov (Russian: Стефан Козлов, /ˈstɛfɑːn ˈkɒzlɒv/ 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.

Stefan Kozlov

Kozlov at the 2022 BNP Paribas Primrose Bordeaux
Country (sports)	United States
Residence	Pembroke Pines, Florida, United States
Born	(1998-02-01) 1 February 1998 Skopje, Republic of Macedonia
Height	1.83 m (6 ft 0 in)
Turned pro	2013
Plays	Right-handed (two-handed backhand)
Prize money	$1,005,853
Singles
Career record	9–26 (25.7%)
Career titles	0
Highest ranking	No. 103 (July 18, 2022)
Current ranking	No. 653 (March 18, 2024)
Grand Slam singles results
Australian Open	2R (2022)
French Open	Q2 (2017)
Wimbledon	1R (2022)
US Open	1R (2022)
Doubles
Career record	0–5
Career titles	0
Highest ranking	No. 180 (June 19, 2017)
Grand Slam doubles results
US Open	1R (2014)
Last updated on: March 30, 2024.

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.

Personal life

He is the son of Russian parents and his father Andrei is a tennis coach.

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 wildcard 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 in 2016

In 2013, Kozlov made his ATP World Tour debut as a wildcard at the Newport tournament 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 2014 in Sacramento, where he lost to Sam Querrey. He also reached seven career ITF Futures finals and won four of these finals.

2016-17: First ATP win and quarterfinal, Two Challenger titles

In April, Kozlov reached the final at the Open de Guadeloupe. In June, he won his first career ATP level match as a wildcard at the 2016 Ricoh Open in Den Bosch. He reached his first career quarterfinal by defeating Steve Johnson in the second round. Toward the end of the season, Kozlov reached a second Challenger final on the year at Suzhou. He won his first career Challenger event in Columbus. He won his second title at the 2017 Las Vegas Challenger.

2021: First three Challenger titles since 2017, return to top 200 since 2018

In September, at the 2021 Columbus Challenger, Kozlov won his first title in four years, defeating Max Purcell in the final in three sets. At the same tournament he won also in doubles partnering Canadian Peter Polansky. He followed this by a final at the 2021 Las Vegas Challenger and a second Challenger title for the season at the 2021 Charlottesville Men's Pro Challenger, defeating another Australian Aleksandar Vukic. As a result, he returned to the top 200 in more than three years at No. 188 on November 8, 2021. He ended the year with winning his third Challenger in Champaign, US. As a result he finished the year ranked World No. 159 on 22 November 2021.

2022: Grand Slam debut & first win, second ATP quarterfinal & career-high ranking

At the 2022 Australian Open he made his debut as a wildcard and won his first Grand Slam match against Jiří Veselý. He lost in the second round to 7th seed Matteo Berrettini.

As a qualifier at the 2022 Delray Beach Open, he reached his second career quarterfinal after defeating Emilio Gómez and Steve Johnson.

Ranked No. 130 at the 2022 Abierto Mexicano Telcel in Acapulco, he reached the main draw as lucky loser and defeated Grigor Dimitrov in a stunning upset in three sets after fighting cramps, in the longest match in Acapulco history. It was the biggest win in his career.

At the 2022 Wimbledon Championships, he made his debut at this Major when he entered the main draw as a lucky loser after the late withdrawal of Borna Ćorić. Kozlov lost in straight sets to 12th seed Diego Schwartzman. He reached a new career high ranking of No. 103 on 18 July 2022.

ATP Challenger and ITF Futures finals

Singles: 18 (9–9)

Legend (singles) ATP Challenger Tour (5–5) ITF Futures Tour (4–4)

Titles by surface Hard (9–9) Clay (0–0) Grass (0–0)

Result	W–L	Date	Tournament	Tier	Surface	Opponent	Score
Loss	0–1	Oct 2014	Sacramento, USA	Challenger	Hard	Sam Querrey	3–6, 4–6
Loss	0–2	May 2015	USA F15, Orange Park	Futures	Hard	Darian King	2–6, 6–3, 0–6
Loss	0–3	May 2015	Mexico F3, Mexico City	Futures	Hard	Iván Endara	1–6, 6–7(3–7)
Loss	0–4	Oct 2015	Belarus F3, Minsk	Futures	Hard (i)	Dzmitry Zhyrmont	1–6, 4–6
Win	1–4	Oct 2015	Belarus F4, Minsk	Futures	Hard (i)	Dzmitry Zhyrmont	6–1, 7–6(7–1)
Win	2–4	Jan 2016	USA F1, Los Angeles	Futures	Hard	Philip Bester	7–6(9–7), 6–7(3–7), 6–3
Win	3–4	Mar 2016	Canada F2, Sherbrooke	Futures	Hard (i)	Lloyd Glasspool	4–6, 6–4, 6–4
Loss	3–5	Apr 2016	Le Gosier, Guadeloupe	Challenger	Hard	Malek Jaziri	2–6, 4–6
Win	4–5	Apr 2016	USA F13, Little Rock	Futures	Hard	Eric Quigley	6–7(3–7), 6–3, 7–6(12–10)
Loss	4–6	Oct 2016	Suzhou, China	Challenger	Hard	Lu Yen-hsun	0–6, 1–6
Win	5–6	Nov 2016	Columbus, USA	Challenger	Hard (i)	Tennys Sandgren	6–1, 2–6, 6–2
Win	6–6	Oct 2017	Las Vegas, USA	Challenger	Hard	Liam Broady	3–6, 7–5, 6–4
Loss	6–7	Mar 2019	M25 Calabasas, USA	World Tennis Tour	Hard	Alexander Ritschard	2–6, 6–0, 6–7(5–7)
Win	7–7	Sep 2021	Columbus, USA	Challenger	Hard (i)	Max Purcell	4–6, 6–2, 6–4
Loss	7–8	Oct 2021	Las Vegas, USA	Challenger	Hard	J. J. Wolf	4–6, 4–6
Win	8–8	Nov 2021	Charlottesville, USA	Challenger	Hard (i)	Aleksandar Vukic	6–2, 6–3
Win	9–8	Nov 2021	Champaign, USA	Challenger	Hard (i)	Aleksandar Vukic	5–7, 6–3, 6–4
Loss	9–9	Oct 2022	Las Vegas, USA	Challenger	Hard	Tennys Sandgren	5–7, 3–6

Doubles: 13 (6–7)

Legend (doubles) ATP Challenger Tour (4–5) ITF Futures Tour (2–2)

Titles by surface Hard (5–3) Clay (1–4) Grass (0–0)

Result	W–L	Date	Tournament	Tier	Surface	Partner	Opponents	Score
Win	1–0	Nov 2013	USA F31, Bradenton	Futures	Clay	Sekou Bangoura	Devin McCarthy Tommy Mylnikov	6–2, 6–4
Loss	1–1	May 2014	Spain F10, Vic	Futures	Clay	Noah Rubin	Sergio Martos Gornés Pol Toledo Bagué	2–6, 5–7
Win	2–1	Jan 2015	Maui, USA	Challenger	Hard	Jared Donaldson	Chase Buchanan Rhyne Williams	6–3, 6–4
Loss	2–2	Oct 2015	Croatia F18, Solin	Futures	Clay	Nino Serdarušić	Zdeněk Kolář Tomas Toman	4–6, 6–2, [6–10]
Win	3–2	Mar 2016	Canada F1, Gatineau	Futures	Hard (i)	Kaichi Uchida	Sebastian Fanselow Adrian Sikora	7–6(7–5), 6–3
Win	4–2	Jul 2016	Winnetka, USA	Challenger	Hard	John-Patrick Smith	Sekou Bangoura David O'Hare	6–3, 6–3
Loss	4–3	Sep 2016	Cary, USA	Challenger	Hard	Austin Krajicek	Philip Bester Peter Polansky	2–6, 2–6
Loss	4–4	Oct 2016	Ningbo, China	Challenger	Hard	Akira Santillan	Jonathan Eysseric Sergiy Stakhovsky	4–6, 6–7(4–7)
Loss	4–5	Apr 2017	Sarasota, USA	Challenger	Clay	Peter Polansky	Scott Lipsky Jürgen Melzer	2–6, 4–6
Win	5–5	Jul 2021	Lexington, USA	Challenger	Hard	Liam Draxl	Alex Rybakov Reese Stalder	6–2, 6–7(5–7), [10–7]
Loss	5–6	Sep 2021	Cary, USA	Challenger	Hard	Peter Polansky	William Blumberg Max Schnur	4–6, 6–1, [4–10]
Win	6–6	Sep 2021	Columbus, USA	Challenger	Hard (i)	Peter Polansky	Andrew Lutschaunig James Trotter	7–5, 7–6(7–5)
Loss	6–7	Mar 2024	Mérida, Mexico	Challenger	Clay	Boris Kozlov	Thomas Fancutt Hunter Reese	5–7, 3–6

Junior Grand Slam finals

Singles: 2 (2 runner-ups)

Result	Year	Championship	Surface	Opponent	Score
Loss	2014	Australian Open	Hard	Alexander Zverev	3–6, 0–6
Loss	2014	Wimbledon	Grass	Noah Rubin	6–4, 4–6, 3–6

Doubles: 1 (1 runner-up)

Result	Year	Championship	Surface	Partner	Opponents	Score
Loss	2014	Wimbledon	Grass	Andrey Rublev	Orlando Luz Marcelo Zormann	4–6, 6–3, 6–8

External links

• Stefan Kozlov at the Association of Tennis Professionals
• Stefan Kozlov at the International Tennis Federation