Sanderson, the patriarch of a successful Canadian lacrosse-playing family and a former player, coach and executive for several NLL teams, died Thursday. He was 62.
In a statement, Rock owner and president Jamie Dawick said the organization was extremely saddened by Sanderson's passing.
"'T', as he was best known to everyone, was with me since Day 1 with the franchise after I bought the team in the summer of 2009," Dawick said. "I learned a lot from T, not only about the game he loved so much, but also about loyalty and respect, something T showed in spades to his players.
"He formed the foundation of how the Toronto Rock operate and build a team and it's the legacy that he will leave behind for us as we move forward. There will never be another like Terry Sanderson, rest in peace my friend."
Sanderson, a native of Orangeville, Ont., took a leave of absence on Nov. 13 after he fell ill.
Dawick became interim GM to allow Sanderson to focus on recovery. Sanderson was surrounded by family members when he died Thursday in Florida, the team said.
"Terry Sanderson was a giant in the sport," NLL commissioner George Daniel said in a statement. "On behalf of the entire NLL, I want to convey our deepest sympathies to the Sanderson family and Toronto Rock organization. The impact of his loss is immeasurable. We are all truly saddened by this news."
Sanderson, who played in the original NLL for Syracuse (1974) and Quebec (1975), began his NLL coaching career in 2000 with the Albany Attack. He also served as a coach at various levels in Calgary, Toronto, Philadelphia, Montreal and Ottawa.
He was GM of the Rock when he won his first Champion's Cup in 2005. Sanderson's son Josh Sanderson and nephew Phil Sanderson were on the championship team.
In 2009, Sanderson won another league title as a coach with the Calgary Roughnecks. He later returned to Toronto and guided the Rock to a Champion's Cup in 2011 as GM and assistant coach.
"It is with heavy hearts the Calgary Roughnecks send condolences to the family of Terry Sanderson," the team said in a statement. "We are deeply saddened to receive the news of the passing of one of lacrosse’s most respected individuals. Terry’s contributions as a player, coach and executive, from the grassroots level to the professional level, were immeasurable.
"He will be greatly missed by the entire lacrosse community and forever be etched in Roughneck history as a member of the coaching staff of the 2009 championship team. Our thoughts and prayers are with all of his family during this difficult period.”
Funeral arrangements weren't immediately released.