 Known for his leadership and ability in the air, Piiroja was named Estonian Footballer of the Year five times, in 2002, 2006, 2007, 2008 and 2009.Piiroja started playing football with his hometown club Rivaal, before moving to Pärnu.He made his Meistriliiga debut on 16 July 1995, five days after his 16th birthday, against Eesti Põlevkivi in the opening match of the season.