2009–2010: Professional debut Dimitar Kuzmanov made his professional debut at Bulgaria F2 ITF Futures Tournament – at age of 15 years and 9 months. Late in season, he played 2 more ITF Futures tournaments and won his first ATP ranking points. He continued to play tournaments at
Tennis Europe and
ITF Junior level and this year is definitely one of his most successful years as a junior player. Kuzmanov rose to No. 1 for Boys U16 in
Tennis Europe Ranking (26 June 2009) and was honored as
"Player of the Tennis Europe Junior for Boys U16 – 2009" becoming the first Bulgarian in the history who had won this prestigious award for this age group. He finished the year as No. 1 in
Tennis Europe Ranking. He continued to play
ITF Junior Circuit and
ITF Futures tournaments. He won the
Academic Tennis tournament, organised by Bulgarian Tennis Federation.
2011: Davis Cup and top 1000 debut The last year of playing
ITF Junior Circuit tournaments was the most successful at this level. Kuzmanov became European vice-champion at
2011 European Junior Championships for Boys U18 – Klosters, Switzerland and played doubles semifinal (Partnering with Miki Jamkovic, SRB) at
2011 ITF Roland Garos Junior Championships – Paris, France. He raised his ATP ranking up to position No. 898 at the year end. 2011 is important as it is the year of Dimitar Kuzmanov's first participation at
Davis Cup Event (vs. Belarus and later vs. Cyprus).
2012: First doubles ITF title He won his first doubles title at ITF Futures F10 Tournament – Antalya, Turkey, partnering compatriot
Tihomir Grozdanov. Late during the season, he played few singles and doubles finals and semi-finals at
ITF Futures tournaments. As a
Davis Cup player he played vs. Albania, Georgia and Macedonia. As a
Davis Cup player he played vs. Finland and Estonia. and made his ATP main draw debut, losing in three sets by the world No. 96
Ričardas Berankis. Partnering with compatriot
Alexander Lazov he played vs. future tournament champions
Matwe Middelkoop and
Wesley Koolhof, losing in three sets. Late during the season, he played five singles finals, one doubles final, one singles and one doubles semi-finals at
ITF Futures level, as well as QF at ATP Challenger Tour
Marburg Open, Germany. As a
Davis Cup player Kuzmanov played vs. Turkey and was nominated to play vs. Tunisia, but he didn't play because of trauma. In March 2021, Kuzmanov reached his first ATP Challenger final at the
Zadar Open in Croatia which he lost 6-2/2-6/6-7(5) to Serbian
Nikola Milojevic. It was the longest Challenger final for the season registered at three hours and seven minutes. A week later, in April, he followed with a quarterfinal showing at the
Open de Oeiras Challenger. Thanks to these great results, he reached his best singles ranking of World No. 237 in singles. Kuzmanov made his Grand Slam debut at the
2021 French Open as a qualifier in singles where he lost to No. 12 seeded Bolivian
Hugo Dellien in three sets. He also entered the qualifications at the
2021 Wimbledon Championships for the first time in his career where he also lost to
Marius Copil in straight sets. He lost in the first round of qualifications to Copil again at the
2021 US Open. Kuzmanov received a wildcard at the
2021 Sofia Open for the sixth year in a row. He defeated
Lorenzo Musetti in a tight three set match over 3 hours to finally record his first win at his home tournament. Kuzmanov became the second Bulgarian to win a match in the main draw in Sofia after Grigor Dimitrov, who won the tournament title in 2017. As a result, he reached a new career-high ranking of No. 218 on 4 October 2021. In the following week Kuzmanov made another strong showing at the
2021 Sánchez-Casal Cup in Barcelona, where he won his maiden ATP Challenger title, becoming just the fifth Bulgarian champion in
ATP Challenger Tour's history and the first since Grigor Dimitrov in 2011. He did not lose a set against former World No. 5
Tommy Robredo, 4th seed
Damir Dzumhur,
Teymuraz Gabashvili and 2nd seed
Alex Molcan en route to the final, in which he beat the top seed
Hugo Gaston 6–3 6–0. As a result, he reached a new career-high ranking of No. 189 on 18 October 2021 breaking into the top 200 for the first time.
2022: First Major qualification win, top 160, Seventh Sofia Open wildcard After losing in the first qualifying round in his first three
Grand Slam appearances in 2021, Kuzmanov recorded his maiden win at that level at the
2022 Australian Open. The Bulgarian advanced to the second round of qualifying after a 4–6 6–3 7–6(5) win over
Daniel Masur before bowing out to
Tobias Kamke in the next round. In February, Kuzmanov defeated the 2nd and 3rd seeds
Hugo Grenier and
Enzo Couacaud at the
Bengaluru Open on the way to his third ATP Challenger final, where he lost in straight sets to top seed
Aleksandar Vukic. In May he reached the third round of qualifying at the
2022 French Open defeating
Flavio Cobolli in three sets, getting one step closer to the main draw. He lost to
Santiago Rodriguez Taverna in the third round of qualifying. Kuzmanov repeated his success at the
2022 Wimbledon Championships, where he once again reached the third round of qualifying, but ultimately couldn't make the step further to his maiden main draw appearance, losing out in four sets to
Enzo Couacaud. At the
US Open he reached the third round of qualifying for the third time in a row but bowed out to the No. 303 ranked ATP tour debutant
Brandon Holt. For the seventh year in a row Kuzmanov received a main draw wildcard at the
2022 Sofia Open, but he couldn't replicate his last year's success and lost in straight sets to qualifier
Ugo Humbert in the first round. He finished the season in the top 200 for the second year in a row at No. 195 on 21 November 2022. Two days later he was confirmed as a participant at the inaugural
2023 United Cup as part of the Bulgarian team.
2023–2025: United Cup debut, Two Challenger titles He won his second Challenger title at the
2024 President's Cup in Astana, Kazakhstan and became the oldest Bulgarian champion in Challenger history (since 1978). As a result he returned to the top 300 in the rankings climbing more than 50 spots up. Paired with
Kazakhstani player
Timofey Skatov Kuzmanov reached the quarterfinals in doubles at the newly established
2025 Crete Challenger defeating top seeds
Christoph Negritu and
Alexander Merino. He also won his third singles title at the
second edition of the Crete Challenger after defeating
Federico Cinà in straight sets in the final. ==Coaching==