Career
He was selected 33rd overall by the Montreal Canadiens in the 2012 National Hockey League Entry Draft. Collberg made his professional debut in the 2010-2011 season, in his native Sweden with Frölunda The Human Context of the then Elitserien (SHL). On March 5, 2014, the Montreal Canadiens traded Collberg and a conditional 2nd round pick in the 2014 National Hockey League Entry Draft to the New York Islanders in exchange for left winger Thomas Vanek and a conditional 5th round pick in the 2014 National Hockey League Entry Draft.