Detroit Red Wing opponents knew better than to mess with Steve Yzerman. Take a cheap shot at him - or any of the other Wings, for that matter - and you'd have to answer to Bob Probert and, in later years, Darren McCarty.
It was an on-ice code of justice, and it's proven so effective over the years that players like Probert, McCarty and Derek Boogaard built careers dishing out punishing hits.
But Boogaard's sudden death Friday five months after a season-ending concussion, and his family's decision to donate his brain to the Boston University project that found Probert had signs of brain trauma resulting from blows to the head, is bringing added scrutiny to fighting's place in the NHL.
"I think the league does a good job. They're trying to limit head shots," Tampa Bay Lightning center Nate Thompson said Monday. "I don't think they can (ban fighting entirely). That's part of the game. It's a physical sport and it always has been. If they take that out of the game that takes a part of the history out of the game."
Like football, hockey is a game of controlled violence. Players are skating full-speed around an enclosed rink, and collisions - some intentional, some not - are bound to happen. Referees are there to make sure transgressions are punished. But when they don't, or don't see them occur, that's when players take matters into their own hands.
Boston's Big Bad Bruins brought the rough-and-tumble style to the ice, and the Philadelphia Flyers' Broad Street Bullies are considered the role models for modern-day enforcers. What people forget is that the Flyers only started beating people up because owner Ed Snider got tired of other teams picking on his.
"That fighting stuff way overshadowed the talent we had on the team," Bob "the Hound" Kelly said. "We don't have talent, we don't win anything."
But the Flyers did win, hoisting the Stanley Cup in 1974 and '75.
By the 1980s, every team had an enforcer or two whose primary role was to protect his teammates by whatever means necessary, whenever necessary.
"These guys are so big and strong," said Dave "the Hammer" Schultz, who often wrapped his hands in tape for protection and set an NHL record in the 1974-75 season with 472 penalty minutes. "We weren't big and strong. I could punch a guy, hit him right in the nose, and he's not going to get a concussion. But I didn't train to punch."
Advances in equipment and rules changes elevated the level of fighting. Schultz said he never would have slammed into opponents shoulder- or headfirst because it would have hurt him. But players now wear helmets with face shields, and football-like padding.
Players can now pass all the way up to their opponents' blue lines, increasing the speed of the game. And like every other sport, the players have been super-sized.
"The game has gotten very fast, much faster than it's ever been," said Stan Fischler, the MSG hockey analyst and leading NHL historian. "And the players are much bigger than they've ever been so, as a result, collisions are at a higher speed."
The NHL has tried to limit the damage from fighting, ejecting and suspending players who leave the bench for a brawl. It also passed the "instigator" rule, slapping a two-minute minor penalty of the player that started the fight - though some say the rule has caused more problems than good because it doesn't necessarily punish the initial troublemaker.
This year, the NHL banned blindside hits that target an opponent's head.
But fights are part of the game's appeal, much like NASCAR's fender-benders or driver spats. While college hockey has made its punishments so severe that fighting has all but disappeared at that level, NHL Commissioner Gary Bettman has made it clear the fisticuffs will never disappear entirely from the pro game.
"We celebrate the big hit, we don't like the big head hit," Bettman said last month. "There is an important distinction because we celebrate body-checking."
And the fighting does serve a purpose, players insist. There are only two referees and two linesmen, and they can't see everything. Without that fear of retaliation, the violence could easily get out of hand.
"It's a tool that you can use to help control what happens on the ice," said Rob Ray, the Buffalo Sabres enforcer whose habit of taking off his helmet, jersey and pads during fights prompted the NHL to punish the practice. "Since they put in the 'instigator' rule, the levels of hitting from behind and head shots and dirty shots and that kind of thing have increased.
"I'm not sitting here saying fighting is the greatest thing in the word, but know it curbed a lot of that type of play," added Ray, now part of the Sabres broadcast team. "If you were going to hit somebody like that, you knew there was going to be somebody you'd have to answer to."
Added McCarty, "What's going to stop a guy from slapping your best player on the wrist or being dirty when there's no retribution to it?"
But as more is learned about the devastating impact of concussions and head trauma, there is growing concern about players' long-term health. Sidney Crosby, the NHL's marquee player, hasn't played since January after absorbing hits in consecutive games. Boston's Patrice Bergeron missed the first game of the Eastern Conference finals with a concussion.
There is no known concussion connection to Boogaard's death, but his family donated his brain to the BU Center for the Study of Traumatic Encephalopathy at his wish. Boogaard was approached by researchers after Probert's death.
"You just wish somehow we could cut down on those concussions," Boston Bruins coach Claude Julien said. "Not necessarily for the game of hockey, but more for the individuals. We know how serious those things are, and somehow they seem to be creeping up in our game. We're trying to find ways to minimize those."
AP Sports Writers Jimmy Golen and Dan Gelston contributed to this report.
Follow Nancy Armour at http://twitter.com/nrarmour