After attending Yokkaichi Chuo Technical High School, Asano joined Sanfrecce Hiroshima at the age of 18 in January 2013.

[12] Asano scored on his debut in an eventual 3–1 home win over Turkish club Yeni Malatyaspor in the first leg of the Europa League third qualifying round.

[13] Partizan eliminated Yeni Malatyaspor and then the Norwegian Molde, thus qualifying for the Group L of the Europa League, with Manchester United, AZ Alkmaar and Astana as their opponents.

Asano played in all European matches for Partizan this season and was also the scorer in the draw with AZ in Alkmaar (2–2) and in the victory over Astana (4–1) in Belgrade.

[14][15] Partizan finished on second place in the Serbian SuperLiga, behind Red Star, and Asano scored four goals in 23 league games.

[18] Having scored 18 goals in 33 league matches for Partizan in the ongoing championship, Asano announced on 2 May 2021 that he had rescinded his contract with the club.

The dominant hosts made it three before the break as Asano chased through the Hoffenheim defence to slot past Baumann - with Antwi-Adjei providing his third assist of the game.

[25] In the final round of the 2022–23 Bundesliga season, Asano helped his team avoid relegation play-offs by scoring and providing an assist in a 3–0 victory over Bayer Leverkusen.

[32] At youth level, Asano won a gold medal at the 2016 AFC U-23 Championship, scoring a brace against South Korea to give his side a 3–2 win in the final.

[36] In March 2018, manager Vahid Halilhodžić left out Asano and Yosuke Ideguchi for friendly matches with Mali and Ukraine in preparations for the 2018 World Cup due to lack of playing time at club level, commenting, "It makes me sad that Asano and Ideguchi are not playing.

[38] In his first match in the 2022 World Cup, Asano scored a goal in the 83rd minute to give Japan an upset victory over Germany.