Mansourian was born in capital. During his career, he played for Singapore S.League clubs: Balestier Khalsa FC and Geylang United along with the persian club Esteghlal F.C.. He moved to Greek club Xanthi in 1998 after Xanthi fans contributed to raise the amount of money needed to complete the transfer. He played for Skoda Xanthi for one and a half seasons, taking part in 23 games. In December 1999, Mansourian went to Apollon Athens for six months where he played seven games and scored once.