Playing career Edit
Sivak began his professional hockey career in Slovakia playing for HK 32 Liptovsky Mikulas of the 1.Liga, the second tier Slovakian hockey league. There Sivak played two years scoring 4 points in 37 games. In the 2001-02 season he started out on HK Dubnica but played the rest of the year with HK Dukla Trencin in the Slovak Extraliga earning 5-2-7 totals in 33 games. In 53 games with HK Dukla Trencin in the 2002-03 season Sivak had 18 points. Between the 2003-04 season and 2008-09 season Sivak amassed 65 goals, 65 assists, and 120 points in 301 Extraliga games with HK Dunkla Trencin, HK Dubnica, MsHK Zilina, and HKM Zvolen.
Sivak started the 2009-10 season with HC Zlin of the Czech Extraliga appearing in 52 games with 2-11-13 totals. The next year with Zlin, Sivak had 2-7-9 totals in 45 games. In the 2011-12 season, he played with MsHK Zilina scoring 21 goals along with 30 assists for 51 points in 55 games. In the 2012-13 season, Sivak's North American pro hockey career started. He played for the San Francisco Bulls of the ECHL racking up 33 goals and 23 assists for 56 points in 64 games. At the end of the season Sivak was promoted to the Worcester Sharks of the AHL, the affiliate to the NHL's San Jose Sharks, where he played 9 games with 4-1-5 totals.