2009-10: De Haas played for the Mississauga Braves Minor Midget team. The Braves captured the GTHL's Kraft Cup as the regular season's best team and won the West Division playoff title. The Braves lost just one game all season, finishing 31-1-4 in the regular season and going 10-0-1 in the West Division playoffs.
2010-11: De Haas skated in 70 games for the Toronto Marlboros midget AAA team in the Greater Toronto Hockey League. He scored 12 goals with 18 assists and had 40 penalty minutes.
2011-12: De Haas played for the Toronto Lakeshore Patriots in the Ontario Junior A Hockey League .He was invited to the selection camp for the Canada East squad in the 2011 World Junior A Challenge but did not play in the tournament and committed to playing college hockey at Clarkson in 2013-14. In 45 games for Toronto Lakeshore he scored 10 goals with 19 assists and had 32 penalty minutes. The Patriots finished third in the South-East Conference's South Division and reached the conference finals in the playoffs. In 21 playoff games De Haas scored 5 goals with 7 assists and had 10 penalty minutes. De Haas was selected in the 14th round (270th overall) of the 2012 OHL Priority Draft. Not among the 210 North American skaters in Central Scouting's final rankings prior to the 2012 NHL Draft, he was selected by Detroit in the sixth round (170th overall).
Very smooth skater and passer who needs to work on his defensive zone play.
Will join the BCHL's Penticton Vees before moving on to Clarkston University in 2013-14.