On January 20, 2015, Iwasa was selected in the fourth round (65th overall) of the 2015 MLS SuperDraft by the Montreal Impact.[3] However, he was cut during training camp and offered a contract with Montreal's USL affiliate, which he declined. Two months later, he signed a professional contract with his hometown club Sacramento Republic FC.[4] He made his professional debut the following day in a 4–2 defeat to Seattle Sounders FC 2.[5][6]
During the final game of the season, Iwasa scored his 60th USL goal, securing a tie in the match. Following the 2021 season, Iwasa announced his retirement from playing professional soccer.[9]
Personal life
Iwasa was raised in Sacramento's College Greens neighborhood. His grandfather is of Japanese descent.[10]