Dale Hunter, 55, whose son Dylan is an assistant, has an O.H.L.-best career coaching winning percentage of .701. With him or his brother Mark behind the bench, London has won three O.H.L. titles and the 2005 Memorial Cup, awarded to the champion of Canada’s top junior leagues.

“He treated me how he knew I would be treated at the next level,” the Maple Leafs’ Kadri said of Dale Hunter, who played 19 feisty seasons for Quebec, Washington and Colorado and is the only player in N.H.L. history to amass 1,000 points and 3,000 penalty minutes. “As far as mentorship goes, he allowed me to be creative and have that offensive instinct, but he treated me like a man.”

Hunter’s philosophy?

“I really believe it’s a 200-foot game,” he said, citing the length of a rink. “You’ve got to play both ends of the ice. They’ve got great skill, and everybody wants to score. But if you want to have a long career. ...”

He did not finish the thought. But across the N.H.L., it is understood.

“They’re all about allowing players to express their offensive creativity,” said Don Maloney, who was the general manager of the Coyotes when the team drafted Domi and the current London captain, Christian Dvorak, “but they understand that at the pro level, there’s certain requirements you have to have defensively, or else you don’t play.”

Finding examples to show their players requires that Hunter and his staff watch hours of N.H.L. game footage.