He first came to prominence the following year, as he scored 19 goals in 33 games (including a decisive winner in the final match against Eintracht Braunschweig) to help Hannover reach the play-off for the promotion in 2.

[10] Despite having rarely hit double figures again during his prolonged time in Gelsenkirchen, the forward instantaneously became a favorite of supporters, thanks to his qualities both on and off the pitch, his good relationship with team-mates and coaches (especially Huub Stevens, who managed Asamoah for three years at Schalke) and his contributions to the club's successes during the first half of the 2000s.

[12][13] During his time with the Kiezkicker, he played regularly and scored six goals in the league, including a winner that allowed his team to obtain their first away victory against cross-city rivals, Hamburger SV, since 1977.

[16] However, the following year turned out to be more difficult than expected: Asamoah went goalless during the entire season, while the Kleeblätter finished at the bottom of the table, having won only four of their 34 league games, none of which were at home soil.

[8] In May 2001, Asamoah received his first senior call-up for the Germany national team by coach Rudi Völler and subsequently won his first international cap during a friendly match against Slovakia, making him the first African-born black player to ever play for the side: in fact, Erwin Kostedde and Jimmy Hartwig, two previous internationals with black ancestry, were both born in Germany to African-American fathers and German mothers.

[18] Having previously served as a supervisor for the marketing area at Schalke while he was still playing for their reserve team, Asamoah was offered a role as assistant coach for the Royal Blues' U-15 squad immediately after his retirement, in July 2015.

[23][24] In May 2021, the new-established sporting director Rouven Schröder decided to appoint Asamoah as Schalke's first-team manager for the following season, in collaboration with head coach Dimitrios Grammozis.

[8][26][27] On 13 January 2016, Asamoah accepted the 2015 FIFA Fair Play Award on behalf of football organizations and clubs around the world, as he worked to support refugees in the face of conflict.

[29][30] In February 2020, Asamoah firmly condemned the racist insults directed towards opponent defender Jordan Torunarigha by Schalke supporters during a home cup match against Hertha BSC.

[31] In June 2020, Asamoah joined the group of players and board members across Bundesliga who reacted and manifested support to the protests across the United States and the world following the murder of George Floyd, saying quote: "If you have never experienced racism, you'll never find out what that truly means.