John Gallant began his lacrosse career with the Brantford Minor Lacrosse Association Warriors where he was first coached by Gaylord Powless. After playing Junior ’B’ with the Brantford Posse, he spent three years, and was a team Assistant Captain, of the Six Nations Arrows Jr ‘A’ lacrosse team where they represented Eastern Canada in the 1998 Minto Cup Championship. John was awarded the John “Gus” McCauley Memorial Award as the Ontario Lacrosse Association Outstanding Defensive player in 1999.
While playing with the Victoria Shamrocks, John won the Mann Cup, emblematic of the Canadian Senior Lacrosse Championship, in 2003 and 2005. He joined the Washington Power of the NLL in 2002 and moved to Denver, Colorado as the Power became the Colorado Mammoth in 2003. John was part of the Mammoth for the 2006 NLL Championship win under coach Gary Gait.
In 2007 John was a member of Team Canada, winning the World Indoor Lacrosse Championship in Halifax, Nova Scotia. He was also an NLL All Star in 2007 and Mammoth Captain in 2010 and 2011.
John retired from the Mammoth as the team’s all-time leader in games played and ground balls after the 2015 season. He began his high school lacrosse coaching career in 2015 as Assistant Varsity Coach at Valor Christian High School, winning the 2016 Colorado 4A State Championship. In 2016, John was named Head Coach at Rock Canyon High School in Highlands Ranch Colorado.