Career
As a youth player Nikolajs Kozačuks played for his local club, being included in the first team squad for the 2003 season. The youngster played there till 2006 and during these 4 seasons was mainly used in the reserve team, although in the 2005 season he played 13 first team matches in the Latvian Higher League. In January 2007 he moved to the Czechoslovakian 2.
Liga, signing a contract with Football Club Vítkovice.
He played 8 matches for the club and left it at the end of the season, joining the Latvian First League club in July 2007. In the 2008 season he was the club"s top scorer with 8 league goals as the club finished the season in the 8th position of the league table.
As refused to play in the Latvian Higher League for the upcoming season, Kozačuks started the 2009 season with the Latvian First League club FK Tukums 2000. In July 2009 he moved to the Azerbaijan Premier League club Olimpik-Shuvalan, signing a two-year contract.
Failing to establish himself as a first eleven player, at the start of 2010 Kozačuks returned to Ventspils, signing a contract with the Latvian Higher League club Football Club Tranzit.
In summer 2010 he moved to the Israeli Liga Leumit and joined. Kozačuks changed clubs within the league in February 2011, when he was transferred to Ahva Arraba. In July 2011 he returned to his local club before the 2011-2012 Union of European Football Associations Europa League campaign.
Kozačuks was included in the entry for the 2012 season of Daugava Rīga, but did not appear in a single match throughout the season.
In 2013 he became a first eleven player, appearing in 9 league matches. In July 2013 Kozačuks moved to the Polish I liga club Górnik Łęczna.