In his youth years, Assehnoun played for
Pitäjänmäen Tarmo,
HJK Helsinki,
Pallokerho-35,
PK-35 Vantaa and
FC Espoo. His first senior team was FC Espoo, competing in the third-tier
Kakkonen. In 2018, Assehnoun joined Veikkausliiga side FC Lahti, signing an initial two-year contract with the club. In July 2021, he signed a one-year contract with Dutch club
FC Emmen. In July 2023, Assehnoun joined newly promoted Danish club
Vejle on a two-year deal. After half a year at Vejle, Assehnoun was loaned out to
Super League Greece side
Volos FC until June 2024 without any purchase options. In the summer of 2024, Assehnoun returned to Vejle. On 5 July 2024, he signed with Volos on a permanent deal for an undisclosed fee. ==International career==