Harnett 23, played his minor and junior lacrosse in Orangeville and is currently playing for the Calgary Roughnecks. He joined the Roughnecks this season along with Adanac scorer Darryl Veltman in a blockbuster , trade involving former Adanac Josh Sanderson moving to the Boston Blazers.
Harnett joined the Blazers in 2009 as a 20-year-old playing every game and being named to the NLL All-Rookie team. He was still playing Junior A lacrosse in Orangeville, where he eventually won two Minto Cups. He was a finalist for the Canadian Junior Defender of the Year in 2009. Last summer he suited up for the Kitchener-Waterloo Kodiaks. He also played field lacrosse at the University of Guelph, where he was named an All-Canadian by the Canadian University Field Lacrosse Association. He also spent two years at Adrian University in Michigan.