Upon the Selke's introduction in 1978, and Gainey winning it the first four years of its existence, it was seen more as an award that rewarded a forward's defensive excellence. Today, Cassidy said, the prize is more about two-way play.
"You have to put up numbers to get nominated, which speaks to just how difficult it is to play on both sides of the puck," he said.
In Bergeron's Selke-winning seasons of 2012, 2014, 2015 and 2017, he scored 22, 30, 23 and 21 goals and 64, 62, 55 and 53 points. This season, he had 63 points (30 goals, 33 assists) in 64 games.
"[Bergeron] plays against the other team's best line just about every night," Cassidy said. "We try to unburden him from time to time so it's not too stressful over six and a half months, but he's up for the task every night."
Cassidy is having some of the younger Bruins follow Bergeron and captain Zdeno Chara in the gym, "learning things that they can emulate. These are guys you need to learn from. Learning from the best is invaluable.
"[Bergeron] can dig deep. It's well documented how much pain he's played through. He's the guy who can always dig a little deeper, and he does. This guy has already won. He's been there but he wants it again and again and again. That's what you want these young guys to appreciate. You want them to feel his pain as well."
Bergeron is enjoying the moment, one he's experienced the past six years.
"The first year I was just trying to soak everything in, which I'm still trying to do," he said. "I know a little more what's expected and what will unfold. But I'm always humbled to be nominated. It's a cliché to say this, but it's the truth: You're here because of your teammates and the work that you do as a team and the success that you have. I appreciate this and I'm very thankful for it."