Mongolia Ganbayar started playing football at age 7. He first joined the youth team of
Khoromkhon FC of the
Mongolian Premier League in 2014. That year, the senior team won the league championship in the playoffs after being tied on points with
Erchim FC (but with an inferior goal differential) following the regular season. During the
2015 Mongolian Premier League season, he scored 15 goals in 11 matches. Ganbayar also competed in the
Mongolian Football Federation Under-17 youth division in 2015 and was named the best forward in his division of the tournament. In May 2014, Ganbayar was named the best player in the under-15 category of Sensation-2020, an annual national high school football tournament under the auspices of the
president of Mongolia. In this eighth edition of the tournament, he became the first player from a rural area to win the award. Ganbayar appeared in both of Khoromkhon's matches during
2016 AFC Cup qualification. and played to a scoreless draw against
Druk United of
Bhutan. Ganbayar was the youngest player to compete at the tournament. In 2016, he scored 11 goals in 12 league appearances He once again also competed in the Youth Division in 2016 and was named the top forward in the Under-17 age division.
Early experience abroad In 2011, Ganbayar participated in junior camps held by Italian
Serie A club
AC Milan in the Mongolian capital of
Ulaanbaatar. He was one of four players out of over 200 who were invited to participate in the final youth tournament in
Milan. Because of his performances with the Mongolia Under-14 team in 2013, he attracted interest from
Académica de Coimbra of the Portuguese
Primeira Liga. In March 2016 Ganbayar, along with fellow Mongolian
Soyol-Erdene Gal-Erdene and
Mongolia national team coach Zorigtyn Battulga, traveled to England to train with
Barnet FC of
League Two for a month at
The Hive Stadium. He tallied two goals and two assists over two matches for the Under-16 side, including an assist against Norwegian club
Stabæk after entering as a late substitute and two goals and an assist against
Fulham.
Hungary In September 2016, it was announced that Ganbayar had accepted a year-long residency with the youth academy of
Puskás Akadémia of
Hungary's
Nemzeti Bajnokság II. The club competed in the
Nemzeti Bajnokság I, the top division of Hungarian football, before being relegated following the
2015–16 season. He and three fellow Mongolians were chosen for the residency as part of a partnership between the Mongolian Football Federation and the
Hungarian Football Federation initiated in 2014. Ganbayar and his three compatriots became the first players from Asia to ever play at the academy. For his first year at with the club, he was only eligible to compete in friendly matches. On 21 January 2017 he was in the starting lineup as the under-17 team played a friendly match against the under-17 side of Croatian
Prva HNL club
NK Osijek. The match ended in a 3–2 victory for Puskás. He also featured in friendlies against the academies of
FK Senica of Slovakia and Czech clubs
SK Slavia Prague and
FK Dukla Prague. He scored a goal for his club on 14 February 2017 in a 3–1 victory over
Székelyföld Labdarúgó Akadémia. In May 2017 it was announced that three of the four Mongolians who spent the year at the academy were going home to Mongolia. Ganbayar was the only player to remain and was at that time announced as part of the under-17 squad for the upcoming
2017 Puskás Cup. He appeared as a second-half substitute in the tournament's opening match, a 1–0 victory over German giants
FC Bayern Munich. The side's only goal was scored seven minutes after Ganbayar took the field. Ganbayar made his next appearance in the tournament as a second-half substitute against
Budapest Honvéd in the bronze medal match. Puskás earned the eventual victory 7–6 on penalties, with Ganbayar converting the team's second penalty kick. By winning the bronze, he became the first Mongolian to win a medal in a European competition. In the offseason following the Puskás Cup in June 2017, Ganbayar returned to Mongolia. He would return to Hungary in August 2017. Because he was not previously signed to a contract, he could not compete in league matches for the club. However, he signed a contract before returning to Mongolia, making him eligible to compete in the under-19 league the following season.
Loan return to Mongolia On 11 April 2018 it was announced that Ganbayar had returned to Mongolia on loan to play for
Ulaanbaatar City FC on a one-year,
₮6,000,000 per month contract until October 2018. On 23 April 2018, in his first competitive match with the club, Ulaanbaatar City FC won the 2018
Mongolia Super Cup 4–2 over
Erchim FC. He made his league debut for the club on 28 April 2018 in a 1–1 draw with
Arvis FC on matchday 1. Ganbayar scored his lone goal of the brief stint on 10 June 2018 against
Selenge Press FC.
Return to Hungary Ganbayar returned to Hungary in early August 2018 after making two league appearances and scoring one goal for Ulaanbaatar City FC. Only a few days later he participated in the 2018 Honved Cup with Puskás Akadémia FC's under-19 side. He came on as a first-half substitute in the team's opening match against
Brøndby IF of
Denmark. The match ended in a 0–1 defeat. The next day he was named a starter and played the full match against
FK Partizan of
Serbia. Puskás was defeated again, this time 0–4. After placing third in Group A, Puskás Akadémia FC faced
Molde FK of
Norway in the consolation match. Ganbayar again played the full match as the Hungarian side earned a 3–0 victory and fifth place in the tournament. On 24 August 2018 it was announced that Ganbayar had officially signed a youth contract with the club, becoming the first Mongolian player to sign for a fully professional club in Europe. Six days after his 18th birthday, he made his league debut for the under-19 team. After coming on as a second-half substitute against
Debreceni VSC's under-19 side, Ganbayar scored his first league goal for the club six minutes later in the eventual 1–3 defeat. Ganbayar scored his first brace in the team’s next match, a 5–1 victory over
Ferencvárosi TC. Overall, he also scored seven goals in 26 matches for the reserve team in the
NB III over two seasons.
Aqvital FC Csákvár In July 2020, it was announced that Ganbayar had joined
Aqvital FC Csákvár of the
Nemzeti Bajnokság II, Hungary's second tier league, on loan. On the 8th of that month he appeared in a 6–0 pre-season friendly victory over
FC Tatabánya. He scored the team's fourth goal for his first tally for the club. He then appeared in a 2–1 friendly victory against
Békéscsaba 1912 Előre eighteen days later. Ganbayar made his league debut for the club on 2 August 2020, coming on as a second-half substitute in the team's opening match of the
2020–21 NB II season. The away match ended in a 0–3 defeat to
Gyirmót FC Győr. Ganbayar scored his first league goal for the club on 23 August 2020 in an eventual 2–2 draw with
Kaposvári Rákóczi FC. In late August 2020, Ganbayar was loaned back to
Puskás Akadémia FC and named to the senior squad to face
Sweden's
Hammarby IF in the teams' opening match of
2020–21 UEFA Europa League qualification. However, ultimately he did not make the trip to Sweden with the team.
KFC Komárno In July 2021 Ganbayar was loaned to
KFC Komárno of the Slovak
2. Liga for the
2021–22 season. He scored his first goal for the club on 17 July 2021 in a friendly against MŠK Hurbanovo. Ganbayar remained on loan to the club until August 2024 at which time it was announced that the move had been made permanent. The previous season, he helped the club earn promotion to the
Slovak First Football League, the highest level of football in
Slovakia. Ganbayar made his top flight debut for Komárno in a 4:1 loss against league champions
Slovan Bratislava, providing an assist for
Jakub Sylvestr. ==International career==