In 2004, Kooy played a championship season with Mount Royal College (Voted ACIC All Canadian) and the Calgary Mustangs in the old USL First Division.

He also played with Canadian senior amateur side Calgary Callies in the Alberta Major Soccer League, with whom he won National Club Championships in 2003, 2007 and 2008.

After a brief trial with Scottish first division club Livingston in 2008,[1] Kooy was signed by FC Edmonton of the new North American Soccer League, and took part in their 2010 exhibition season in preparation for the team's entry into the NASL in 2011.

After playing professional indoor soccer for the Calgary United in the Canadian Major Indoor Soccer League in 2009 and 2010, he made his debut for Edmonton in the team's first competitive game on April 9, 2011, a 2–1 victory over the Fort Lauderdale Strikers.

[2] He scored his first professional goal on May 11, 2011 in a 1–1 tie with FC Tampa Bay.