Hockey has been a dynamic, changing game throughout the course of its history, but the one constant has been the toughness of its players, in some form or another. 

From goaltenders of the early eras who believed masks were not an option due to the way they restricted vision, despite pucks flying through the air at high speeds, to the biggest, baddest enforcers of the 1990s, hockey has never been without its share of tough guys. 

Over the years, we've seen players overcome dramatic personal obstacles, stand up for superstars and rack up more than 3000 penalty minutes over the course of a career.

In some way or another, these personal milestones have only made NHL players even tougher. 

Of course, hockey has seen many aggressive players who consistently or dramatically crossed the line, and as a result of their dirty play, they were not considered for this list. This includes players like Marty McSorley, Chris Simon and Todd Bertuzzi.

But when it comes to embodying the spirit of the sport in a clean, aggressive manner, these 50 are in a league of their own.

50. Saku Koivu

Most everyone else on this list will be bigger than Saku Koivu. They will be fighters and hitters and all-time penalty minute leaders.

But Saku Koivu earns a spot in the 50 toughest hockey players because of a different kind of toughness, one that even the most fearless enforcer would never want to have to display. 

Not long before the 2001-02 season began, Koivu experienced erratic health problems and violent vomiting. Doctors would diagnose Koivu with non-Hodgkin's lymphoma, an illness that threatened not only his NHL career, but also his life. 

Amazingly, Koivu not only beat the disease, he managed to return for Montreal's final three games of the season. This Finnish warrior proved his toughness in a way that most hockey players will never have to.

49. Craig MacTavish

Like Koivu, Craig MacTavish may not have conventionally earned a spot alongside the NHLers who will follow him in this list, but his distinction in the sport is too good to pass up.

When the NHL made helmets mandatory in 1979, the league included a grandfather clause that allowed active players to choose not to wear them if they wished. MacTavish was a spritely 21 year-old at the time and chose not to don the new domes.

Nearly two decades later, when MacTavish retired from an NHL where every player wore a helmet, MacTavish was the last one who didn't.

For young fans watching the NHL in the '90s, MacTavish seemed a strange traveler from a distant, ancient world.

48. Shea Weber

Weber is one of the younger additions to this list, but he is on the fast track to becoming one of hockey's legendary tough guys. 

We all know about his blistering slapshot and his occasional unchecked aggression, but the most impressive part of Weber's toughness is his durability. He averaged over 26 minutes of ice time per game last season, and has played at least 78 games in each of his last four seasons.

Weber may not be an iconic aggressor quite yet, but there are few men in the NHL right now who look forward to facing him on the ice. 

47. Dominik Hasek

Hasek's brains have always been more intriguing than his brawn, and he doesn't come off as a goalie with a Patrick Roy-level of toughness. However, up until very recently, Hasek was still playing the game.

Goaltenders rarely have this kind of longevity, and the Dominator was reportedly considering an NHL return as recently as this past season. Hasek is 47 years old and has played 28 seasons of professional hockey in his career, and it would have been 29 without the 2004-05 NHL lockout. 

That kind of durability is also as insane as the man himself.

46. Ian Laperriere

Laperriere is seen here sporting a full face mask that he had to wear for the 2010 postseason as a result of taking a shot to the face in the first round against the New Jersey Devils, the second time that season that Laperriere suffered such an injury.

Post-concussion symptoms as a result of the errant puck would ultimately drive Lappy to an early retirement, but he had left his mark on the game. Laperriere was known by every team he played for as a true warrior, a player who was willing to sacrifice the body to a fault.

45. Mario Lemieux

Mario Lemieux faced a situation very comparable to Koivu's when he was forced into aleave of absence after being diagnosed with Hodgkin's lymphoma, and would retire early as a result of chronic back problems. Amazingly, he overcame all these health issues to become hockey's seventh-leading scorer of all-time.

Mario has consistently shown toughness in his personal life, on the ice, and in an executive role, when his commitment to the fledgling Pittsburgh Penguins kept the team in western Pennsylvania and allowed for the resurgence in popularity that came with the arrival of Super Mario's successor, Sidney Crosby.

44. Dave Manson

Dave Manson played 16 NHL seasons as a hard-hitting, give-'em-hell kind of defensemen for teams like the Chicago Blackhawks and the Toronto Maple Leafs. 

The journeyman defenseman played a fearless game despite his mid-range size, and he currently sits 13th all-time on the penalty minutes list with 2,785. He sits between good, albeit more recognizable company with Scott Stevens 151 PIMs behind him and Chris Chelios 7 PIMs ahead.

43. Owen Nolan

Despite dealing with various injuries that prevented him from ever playing a full season in the NHL, Owen Nolan remained in the league from 1990 until 2010.

The hard-nosed winger was the epitome of a high-scoring power forward, playing a style of game that sent him to crash the corners and the crease, using his solid frame to muscle his way to as many as 84 points per season. 

He played for seven different teams in his NHL career, and the journeyman left a lasting impression on seven different cities in his time.

42. Adam Foote

Playing on Avalanche teams that featured the likes of Joe Sakic, Peter Forsberg and Rob Blake, Adam Foote was an easy player to overlook, but he quietly did his job better than anyone else.

While the rest of his teammates were making headlines and capturing hearts in the hockey world, Adam Foote was clearing out the crease in front of Patrick Roy and giving up his body to block shots. 

He would eventually succeeded Sakic as team captain and remained in the NHL until the 2010-11 season.

41. Rick Tocchet

Rick Tocchet played for six different NHL teams in his career, and as he bounced around the NHL, he managed to rack up 2,972 PIMs thanks to his unapologetic style of play. 

Tocchet had more than his fair share of offensive talent, but aggression was where he truly shone. Fans from Pittsburgh to Philadelphia to Phoenix recall and appreciate the tough-guy attitude of one of the better power forwards of the '80s and '90s.

40. Stu Grimson

Standing at 6'6" and 240 pounds before he even managed to put his skates on, Stu Grimson was destined to be a big-time enforcer during hockey's heyday for fighters. 

Grimson bounced around the NHL, beginning his career in Calgary and ending it in Nashville, and despite 729 career games, Grimson has a whopping 39 points to his name. But the Grim Reaper was never put out onto the ice to score goals; his mission was to throw punches.

And few men at any point in NHL history were better at it.

39. Jeff Beukeboom

Jeff Beukeboom's career was cut short by the effects of post-concussion syndrome, but before having his bell run one too many time, the towering defenseman made his impact on the NHL.

Beukeboom won four Stanley Cups in his career, helping his team by delivering devastating hits in the defensive zone and keeping the crease clear for his goaltender. He played the game, and he played the game hard, literally up until the point that his body could no longer take it.

38. Gino Odjick

Amazingly, Gino Odjick sits 17th on the all-time penalty-minutes list, despite the fact that he only played 605 career NHL games. Few players have made a bigger tough-guy impression in such a short span of time.

His fisticuffs became a mainstay for teams like the Vancouver Canucks, with whom he put up three separate seasons with more than 300 penalty minutes.

37. Jarome Iginla

Calgary's captain wowed hockey fans in the early 2000s, becoming the increasingly-rare breed of player who simultaneously specializes in scoring and the more aggressive elements of the game. 

Iginla won the Art Ross Trophy in 2002, but he is just as well known for his ability to lead by example. Iginla has never been shy about dropping the gloves or throwing the body around, and though his career is starting to wind down, he remains one of the true gems of the sport.

36. Bryan Watson

Bryan Watson was an undersized defenseman who played a big game. 

Standing at 5'9", Bryan didn't strike one as the typical stay-at-home defenseman, but his style of play was so outstandingly aggressive that it became easy to forget what he lacked in size. 

In his journeyman career, Watson managed to rack up over 2000 PIMs.

35. Zdeno Chara

Zdeno Chara is the complete antithesis of Bryan Watson.

Chara is the biggest player in NHL history, standing 6'9" tall and serving as one of hockey's most imposing defensive players. Instead of playing an overly aggressive game, Chara is actually more on the reserved side; his size just makes him manhandle any opponent easily.

Without truly trying, Chara still qualifies as one of hockey's greatest tough guys.

34. Billy Smith

Few goalies will appear on this list due to the nature of the position, so you can bet your bottom dollar than the few who make it on here are truly and wonderfully insane. 

New York's Billy Smith is one of the great examples of a goaltender who just didn't give a $%#@, clearing out his own crease by slashing his stick at opponents and even going so far as to charge his own teammates when he didn't like the way they shot at him during practice. 

33. Rob Blake

Rob Blake became a shining example of leadership in hockey during his tenure in the league, but he also became widely known for his toughness. 

Blake was a shot-blocker extraordinaire, and used his 225-pound frame to keep his goaltender's lines of sight open. Blake was the epitome of a composed, yet aggressive defenseman: as mentally tough as he was physically tough.

32. Tim Horton

Tim Horton was not a large man by hockey standards, but he became a very intimidating player to play against. 

Horton seemed to be freakishly strong and completely willing to use his strength, dropping the gloves frequently and winning fights by getting his opponent in a sort of iron grip to crush them as he latched onto them. 

31. Brendan Shanahan

Nowadays, the Shanahammer is the one dispensing disciplinary action, but it wasn't so long ago that he was a specialist in receiving it. 

In Shanahan's 21 seasons, he racked up 2,489 PIMs, good for 22nd on the all-time list. But Shanahan was a multi-tooled NHL player, using his tough-guy attitude to make aggressive plays on the puck en route to his 1,354 career points. 

30. Derian Hatcher

Derian Hatcher was among the last of a dying breed: the big, brutal defensemen. 

Playing for the Dallas Stars in the years leading up to the NHL lockout, when obstruction rules were more lenient, Hatcher was a specialist. He wasn't a fast player, but his size and strength allowed him to stop anyone trying to sneak by him in the offensive zone. 

Once stringent obstruction rules were instituted following the 2004-05 NHL lockout, Hatcher's style of game became a liability. Still, he left his mark on the game prior to the lockout as one of hockey's truly imposing defensemen. 

29. Ken Daneyko

Ken Daneyko could fall into the same category as Derian Hatcher, though Daneyko was a little more methodical and defensively reliable no matter the circumstances.

He was the epitome of a stay-at-home defenseman, scoring zero goals in four of his final six seasons with the New Jersey Devils. Nonetheless, Daneyko's toughness made him valuable, as he had no fear when it came to clearing the crease for Marty Brodeur.

28. Ron Hextall

Ron Hextall was one of those goalies who didn't seem to realize he was a goalie. 

He enjoyed fighting and scoring goals, causing one to wonder why he didn't go the route of becoming a regular NHL skater instead of a goalie. Still, some of Hextall's highlight-reel worthy moments are made more special given his role, like his assault of Chris Chelios in response to an earlier hit that injured team superstar Brian Propp. 

27. Dave Semenko

Dave Semenko had one of the greatest tough-guy tasks of all-time: protect Wayne Gretzky.

As the Great One was hitting his stride in the 1980s, the Oilers put Semenko in charge of playing the enforcer role, putting his body on the line as an insurance policy for No. 99. Semenko's name won't appear alongside Gretzky's on all those records, but his role did get Semenko's name a spot on the Stanley Cup.

26. Derek Boogaard

Tragically, Derek Boogaard's promising career as an enforcer was cut short a little over a year ago, but the NHL tough guy has made a lasting impression on the NHL.

His untimely death has contributed to the spotlight being placed on the mental and emotional health of NHL players, meaning that Boogaard is posthumously continuing his hockey role: protecting his teammates. 

25. Georges Laraque

During his 13 NHL seasons, Georges Laraque became the epitome of gentlemanly aggression in the NHL. 

Laraque was a classic enforcer, fighting not necessarily out of aggression but as a means of giving his team momentum. This chuckle-worthy video shows a mic'd-up Laraque putting the fighting code of conduct on display for all to see.

24. Glenn Hall

Glenn Hall may not have used his stick as a weapon like Billy Smith or invited himself to every fight on the ice like Ron Hextall, but Hall did something that will never be done again: he played 502 consecutive games, as a goaltender.

This was in the days before backup goalies and that silly headgear we refer to as the mask, yet Hall still managed to start a half-millenium of games in a row, beginning in 1955 and going all the way to 1962. 

Forget penalty minutes, that may be the toughest tough-guy record on the books.

23. Chris Pronger

There are those who would argue that Pronger is a dirty player and therefore should not be on this list, and there is a valid case for that. However, there is no denying the fact that Pronger can be a truly intimidating presence whether he is crossing the line or not.

Towering over opponents at 6'6", Pronger has never been afraid to use his size to rub out opponents in the corner. He has a mean, aggressive snarl on his face most of the game and until very recently, his body could take some serious punishment and keep on trucking.

22. Joe Kocur

Kocur was a part of the Detroit Red Wings' "Bruise Brothers" during the late 1980s and 1990s, teaming up with Bob Probert to make the Red Wings the sort of team you did not want to rub the wrong way.

Kocur got a reputation for truly causing major injury with his punches, even managing to crack Donald Brashear's helmet during a bout. Those thundering punches helped land Kocur the No. 20 spot on the all-time penalty minute list.

21. Red Horner

Red Horner was one of hockey's first enforcers, joining the Toronto Maple Leafs in 1928 as a defenseman enthusiastic to drop the gloves.

After his retirement, Horner was elected to the Hockey Hall of Fame, largely on the basis of his 1,264 penalty minutes, which were an NHL record at the time. Horner had gone eight consecutive years as the league's leader in the category.

20. Patrick Roy

When it comes to goaltenders, Patrick Roy was a special kind of tough.

He had the mental toughness to lead the Montreal Canadiens to a Stanley Cup victory as a rookie, the toughness of personality that allowed him to "decide" when he would be traded out of Montreal, and the physical toughness to enthusiastically take on just about anybody in the league in a brawl. Especially if the opponent was the Detroit Red Wings.

19. Bobby Clarke

The captain of the Broad Street Bullies was never supposed to have made it in the NHL, having begun as an undersized, diabetic farmboy from Manitoba. However, the Flyers took a chance on him, and did it ever pay off. 

Clarke was not the most aggressive member of those Bullies' teams, but the way he commanded the ice as a player of his stature was what made Clarke a true tough guy. He was the emotional leader for hockey's toughest players and was never afraid to get himself into a scrap.

18. Cam Neely

Cam Neely's outstanding career was cut short by knee injuries, but in only 726 games, Neely made a lasting impression on the sport with his skill and his toughness. 

Neely managed to rack up 1,241 penalty minutes in his shortened career and was well-known for his fearless style of play. Had he gotten to play a full slate of games in his career, Neely would likely break the top ten on this list, and many others.

17. Tie Domi

How a 5'10" pest sits third on the all-time penalty minutes list is beyond me, but Tie Domi truly earned his 3,515 career PIMs. 

Domi's career began with the New York Rangers in 1990-91, a year that saw him score one goal and zero assists...and rack up 185 penalty minutes.

That set the tone for the rest of Domi's career, as he would become one of hockey's most frequent travelers to the sin bin.

16. Dale Hunter

Sitting directly above Domi on the PIMs list is Dale Hunter, whose 3,565 penalty minutes are good for second all-time.

Unlike Domi, who would put up 300 or more PIMs in some seasons and much fewer in seasons where his role was diminished, Hunter slowly but surely worked his way up the list by being an everyday player. 

Hunter's 3,565 penalty minutes were only made possible by the 1,020 career points that kept him in the lineup every day. Some guys can simply do it all.

15. Rob Ray

You know you're one of hockey's tough guys when the NHL has to make rules to stop you from having advantages in fights. 

Rob Ray used to intentionally remove his helmet, jersey and pads before the fight to ensure that his opponent would have trouble using Ray for balance. This shifted the advantage to Ray despite his lack of body armor. 

The league eventually made it against the rules to remove jerseys and pads before a fight, a rule that can be directly attributed to Ray's physical dominance.

14. Ted Lindsay

Ted Lindsay retired from the NHL with 1,808 penalty minutes, but his real legacy of infractions against the NHL comes from his role in creating the NHLPA.

It was Lindsay who researched players' rights in other sports and came to the conclusion that hockey players were being denied privileges they deserved, and he helped to form the NHLPA in 1957. 

It's safe to say that Ted Lindsay was a fighter both on and off the ice.

13. Donald Brashear

Weighing in at 240 pounds, Donald Brashear was one of the NHL's true heavyweights from 1994 through 2010. 

In that time, Brashear racked up 2,634 penalty minutes, most of them from fighting and a few of them from his role in starting full-scale brawls. Brashear was a classic enforcer, protecting his teammates through the fighter's code. 

In addition, Brashear continued his NHL career even after falling victim to one of hockey's most brutal assaults, a swinging attack from Marty McSorley that saw the defenseman banished from the league.

12. Wendel Clark

"Captain Crunch" was one of the most aggressive players to ever play in the NHL, and while Clark doesn't sit among the all-time leaders in terms of penalty minutes, that just goes to show how his style of play was every bit as clean as it was intense.

Wendel Clark was known for his legal bone-crushing hits and his ability to lead by example. Perhaps no image of Clark is more iconic than his freight-train impression that victimized Bruce Bell.

11. Bob Probert

The second half of the "Bruise Brothers" had his share of demons off the ice, but when he put on his jersey, Bob Probert was one of the toughest guys out there. 

He sits fifth on the all-time PIMs list with 3,300, amassing as many as 398 penalty minutes in a single season, the sixth-most of all-time. Probert's life was tragically cut short not long after he retired, and his brain was donated to aid with research on the effects of sports injuries to the brain.

10. Clark Gillies

As the New York Islanders built a Stanley Cup dynasty for the 1980s, Clark Gillies played the important role of protecting the Mike Bossys and Denis Potvins of the world. 

Gillies was a fearless enforcer, taking on the NHL's toughest players en route to the Isles' many Stanley Cup championships, and he was not excessive in using his aggression. Because Gillies' skills went beyond what he could do with his fists, he fought sparingly, never registering more than 99 penalty minutes in a season.

9. Terry O'Reilly

The "Tasmanian Devil" was one of hockey's most dramatic and dynamic players in the 1970s and 1980s, as O'Reilly became the epitome of fearlessness in hockey.

O'Reilly was a mid-range player when it came to size, but his energy was unequaled and there seemed to be no way to contain him. Not even the glass at Madison Square Garden could stop O'Reilly, who infamously scaled it to chase a Rangers' fan in a 1979 brawl that saw things go a bit too far.

8. Dave Schultz

Dave "The Hammer" Schultz only played 535 games in his NHL career. 

Somehow, in those 535 games, Schultz served 2,294 minutes in the sin bin.

In fact, Schultz is the only player with more than 2,000 PIMs to have played fewer than ten seasons in the NHL. If that isn't evidence of how Schultz thrived in the Broad Street Bullies role, then nothing is.

7. Larry Robinson

Larry Robinson remains one of the greatest defensemen in NHL history, having the mental and physical toughness to truly excel at the defensive aspect of the game.

Robinson is the only player other than Bobby Orr to ever achieve a plus-minus of plus-100 or better in a season, when he finished a plus-120 in 1976-77. Robinson, while a legitimate scoring threat, was a true defensive specialist, playing a stalwart, methodical style of defense to stifle opposing offenses. 

Few players have ever had Robinson's poise and toughness.

6. Chris Chelios

Hockey keeps track of statistics like penalty minutes, blocked shots, hits and time on ice, all of which can be great indicators of a player's toughness. 

However, when it comes to being tough, there is rarely a substitute for longevity. In a sport like hockey, it is simply not easy to play well past your prime. 

Chris Chelios is the exception, holding the record for most games played by a defenseman with 1,651 played over the course of an NHL-record 26 seasons. The sort of punishment that the human body has to take while playing hockey at age 48 is truly astounding.

5. Eddie Shore

One of hockey's original bad boys, Eddie Shore nearly put himself in the record books in all the wrong ways by fracturing Ace Bailey's skull with a check from behind in 1933. There were initially fears that Bailey could die from the hit, a distinction that even the toughest hockey player in the world likely could not handle. 

Luckily, Bailey not only survived, but publicly forgave Shore for the hit two months later. That sentiment is the only reason that Shore's aggression did not disqualify him for this list on the grounds of being a dirty player. 

On top of that, when Shore's ear was nearly severed in a collision, not only did Shore refuse anesthesia, but he insisted on being given a mirror so he could watch the doctor sew it back on.

Conclusion: Eddie Shore was one tough customer. 

4. Tiger Williams

Those Vancouver Canucks' jerseys are among the ugliest things out there, but somehow putting one of them on Tiger Williams just works. 

Tiger is the NHL's all-time leading penalty-minute man, with an astounding 3,966 PIMs in under 1,000 games. Williams accumulated over 300 PIMs six times in his career. He also managed to rack up 116 of them in the playoffs in 1982. 

As one of hockey's truly great enforcers, Dave "Tiger" Williams is a stand-out tough guy in NHL history.

3. Mark Messier

One of the hardest-hitting players and perhaps the greatest leader in NHL history, Mark Messier is the epitome of toughness in hockey. 

Toughness is not simply being a big body and bulldozing your way to the front of the net, which is something that Messier could certainly do. Instead, toughness is taking on all the elements of being a leader and thriving on them. 

Messier became the darling of a normally hostile New York media, boldly guaranteeing wins and leading the championship-hungry Rangers to the 1994 Stanley Cup Final, where the team won its first Cup since 1940. 

Few players embody toughness the way that Messier did.

2. Scott Stevens

In recent years, the NHL has focused heavily on eliminating hits on unsuspecting players from the game. Before the league began to take action on this, though, these hits were the highlights of the game, and no one delivered them better than Scott Stevens. 

Stevens, who sits 14th all-time on the PIMs list, was perhaps the most brutal clean hitter in NHL history, running over superstars from Paul Kariya to Eric Lindros. 

It is widely agreed-upon that Stevens single-handedly altered the course of Lindros's career. Stevens is hockey history's most tough-as-nails defenseman.

1. Gordie Howe

One of hockey's greatest players is also its toughest.

Gordie Howe is the combination of every tough guy on this list. He could hit as hard as Scott Stevens. He had the leadership of Mark Messier. He combines the longevity of Chris Chelios with the reliability of Larry Robinson, and he never needed a Dave Semenko or Clark Gillies to protect him.

Mr. Hockey is exactly that: the epitome of what we love about hockey.

He was so proficient at scoring, passing and fighting that doing all three in the same game is known as the "Gordie Howe Hat Trick," a goal, an assist and a fight.

When looking for hockey's toughest customer, look no further than No. 9, Mr. Hockey himself.