His previous clubs include Dinamo Zagreb, Vicenza, Como, Fenerbahçe, Galatasaray and Rubin Kazan.
Tomas August 2007, he signed a two-year contract with Russian club Rubin Kazan, for a fee of €4.8 million.
Tomas made his debut for Croatia in an April 1998 friendly match against Poland, coming on as a 60th-minute substitute for Tomislav Rukavina, and earned a total of 49 caps, scoring 1 goal.
He also played for the national team in their third and last game at the 2006 FIFA World Cup against Australia which became his final international appearance.
[4] On 21 June 2022, Tomas was appointed as Head Coach of Moldovan Super Liga club Sheriff Tiraspol.