Kokushikan University
Soma was born in Kawasaki on December 10, 1981. After playing for Verdy Kawasaki (later "Tokyo Verdy") youth team, he went on to Kokushikan University. When he was a Kokushikan University student, he joined J1 League club Tokyo Verdy in 2003. In September 2004, he became a regular left side back instead regular player Atsuhiro Miura left Verdy for Japan national team. Verdy won the champions in 2004 Emperor's Cup. Although Soma also played as regular player in 2005, Verdy finished at the 17th place in 2005 season and was relegated to J2 League.