Coaching or managing a team is an incredibly demanding job and requires a number of different skills. To lead a team of individuals you need to command respect, and much like the teachers you get in school , people go about doing this in different ways. Throughout all the major sports there have been many coaches and managers that strike fear in just about everyone that crosses their path, and using this to lead a team can (sometimes) work to great effect. These coaches may have a tendency to throw tantrums on the sidelines, chew a player’s ear off, confront referees or simply give a deathly stare to whoever has wronged them.

Of course it is not just the players under them that have to tread lightly, it is also the press, as many of these coaches and managers are notorious for their interviews which leave reporters shaking in their boots. These interviews can provide a great source of entertainment for the fans at home, and they can even endear you to the coach or manager who has such a strong vision for how they want the game to be played.

Many of the coaches on this list are perfectionists, which is why they so often appear irate on the sidelines or have no problem getting in the face of their star player. It is also important to note that just because these coaches are terrifying it does not mean that the players do not enjoy playing for them. There is often a tremendous amount of trust and respect in the relationship between player and coach which goes both ways. Gregg Popovich is a prime example of this, as he does not hesitate to shout or give a frosty stare to the likes of Duncan, Parker and Ginobli, but it is clear that everyone on the Spurs roster buys into Popovich’s military like system and they enjoy playing for him.

Here are 20 of the most terrifying coaches in professional sports history across football, hockey, baseball, basketball and soccer. There are many college coaches that would slot into this list, but this will focus on the major professional sports.

20 20. Quin Snyder

Snyder may not be as established in professional sports as the majority of names on this list, but once you have witnessed his demonic scowl then you will soon see why he strikes terror into people’s hearts. He has spent a large part of his career terrifying the students of Missouri and as an assistant coach at teams around the league, but now takes charge of a Utah Jazz team which must be scared to put a foot out of line in case he gives them his evil stare, which looks like something straight out of a horror film. His first technical came in November after chastising his team and screaming at them to wake up; he is certainly one to watch out for this season.

19 19. Ozzie Guillen

Ozzie Guillen was a manager that was constantly in the middle of some controversy, and both his actions and comments stirred these controversies which have earned him a spot on this list. He has a history of saying whatever is on his mind, which makes him intimidating to players, other coaches, reporters and of course the umpires.

It is not just his words that make him an unpredictable person, but he would often get himself ejected for leaving the dugout and causing trouble on the field, kicking an umpire's mask as hard as he can being just one of many examples. He has done and said a number of inappropriate things in his career, and this unpredictability lands him here.

18 18. Jim Playfair

Playfair may have only spent one season as a head coach in the NHL, but his explosiveness and tantrums earn him a spot on this list. Most notable is his meltdown on the sidelines of an AHL game between his Abbotsford Heat and the Hamilton Bulldogs, where his reaction to one of his players being tossed has become an internet sensation. Playfair grabs the nearest stick he can find before repeatedly smashing it until it shatters in half, he then throws the stick onto the ice and rips open his suit jacket as if he is about to transform into The Incredible Hulk, and then stands on the bench and smashes another stick to smithereens. Unfortunately for Playfair this would not fire up his team, who would go on to lose 4-0.

17 17. Roy Keane

Both as a player and manager, Roy Keane struck fear into those that came across him. His hard-nosed playing style translated across to his managerial and even punditry career, but instead of crunching tackles he became famous for a menacing stare and verbal confrontations. A reporter’s mobile phone ringing during a press conference was enough to boil Keane’s blood, who gave the culprit the sort of look a headmaster would give if your phone went off in class, before halting the press conference to shame the reporter. Keane seemed to buy into his terrifying persona by growing a long, bushy grey beard, and it is also rumoured that he recently stormed round the house of Tom Cleverley to confront the midfielder about stories of training ground bust ups that lead to his Aston Villa departure.

16 16. Mike Ditka

Just one look at Mike Ditka and you know not to get on the wrong side of him. Although he had a habit of making reporters laugh during press conferences, everyone knew that one wrong question and the laughter would stop. Iron Mike would often also scream at his team and particularly his quarterbacks, and he also had an ongoing feud during his time at the Bears with defensive coordinator Buddy Ryan. The two reportedly came to blows, even though many consider their 1985 team to be the second-best Super Bowl champion of all time. Ditka’s passion and fire made him a great coach, but also one which many players and reporters feared to be around.

15 15. Louis Van Gaal

Louis Van Gaal is a man supremely confident in his abilities, and this will often see him chastise reporters or players that question his methods. There are countless anecdotes of his outbursts and actions, but perhaps the most terrifying is when he demonstrated to his Bayern Munich team that he could drop any player he wanted to because  he “had the balls”. To demonstrate his point, he dropped his trousers to show his team that he was not lying, and his point was made. His training sessions are also notorious, and it has been reported that he once shouted so hard at one of his players that his dentures came out. Van Gaal is a fine coach and has proven himself over the years, but he is also a coach that is feared by many due to his confrontational manner and history of going perhaps a little too far to prove a point.

14 14. Jim Mora Sr.

Jim Mora is best remembered for his on air rants that he would go on, often leaving reporters stuttering over their own words. He is certainly a coach that has no problem speaking his mind whether he was criticising sports writers, verbally bashing his team’s performance or coining bizarre phrases like “diddly poo”. His most famous moment came in a news conference when he was asked about his team making the playoffs, which elicited an emotional response from Mora who could respond little more than “playoffs?!” Jim Mora went on some spectacular rants in his time which will always be remembered, but for his players and daring reporters he was a coach to tread carefully around.

13 13. Ken Hitchcock

Ken Hitchcock is a no nonsense coach who is known to scream at his players and gives rookies a tough time, and he demands excellence each time his team steps onto the ice. He is also not one to mix his words, snapping at Sabres coach Lindy Ruff after being beaten by the Sabres in Game 2 of the 1999 Stanley Cup Final. Ruff is not the only one to stir anger in Hitchcock, who has also had words with another stern NHL coach, John Tortorella. Luckily Hitchcock seems to have toned down a little in his St. Louis tenure.

12 12. Jerry Sloan

Jerry Sloan was one never to shy away from a confrontation, and his fiery competitiveness often motivated his Utah Jazz team to lift their game. It would sometimes cost the team too though, as over his coaching career Sloan picked up hundreds of technical fouls and was often ejected, and this included physical altercations with referees Bob Delaney and Courtney Kirkland. In the 1999-00 season, Sloan was called for a staggering 29 technical fouls and was ejected seven times. His confrontations with referees, players, reporters and even owners (Mark Cuban once felt the heat) make Sloan one of most intimidating coaches to patrol the sidelines.

11 11. Peter Laviolette

Peter Laviolette is a coach that is all about toughness, which makes him a fan favourite with many. This, and his fiery temper, can make him an intimidating force, and not a coach that you would want to let down as a player. After a late game hit on Danny Briere, Laviolette unleashed hell as he shattered a stick in half by swinging it against the boards, before climbing up the bench to verbally bash then-Penguins coach Dan Bylsma. This perfectly demonstrates Laviolette’s fierce passion and how he always looks out for his players. He recently demonstrated his toughness by taking a puck to the face which left a cut above his eye, but instead of making a song and dance of it he simply got on with the job.

10 10. Bobby Cox

Bobby Cox will always be remembered for holding the record for most ejections, with an astonishing 158 to his name. While this has provided great entertainment for fans, he has given umpires nightmares as they knew that every game there was a good chance he would be up in their face if there was a call he didn't agree with. Having such an explosive manager puts the umpires, players, opposing coaches, reporters and even fans on edge, as at any moment he could fly off the handle and spark ugly scenes. The Hall of Famer was known as a terrific “players” manager and would always stick up for his team, but his eagerness to strike up an argument with anyone else means that he is a manager that was feared by many.

9 9. Jim Harbaugh

Normally when you see a grown man throwing a tantrum it is funny, not terrifying, but this is not the case with Harbaugh. When Harbaugh throws a tantrum he crosses over into terrifying territory, and often it looks like he is about to transform into some kind of monster. It is not just the officials that fear Harbaugh’s wrath, he also gets stuck into opposing coaches and in between player scuffles too. He wears his heart on his sleeve perhaps a little too much, and his bizarre reactions leave people amused, scared and a little bewildered. You would not want to be the one responsible for causing one of his famous tantrums. Oh, and why does he always wear khakis?

8 8. Bill Belichick

Every time Bill Belichick faces reporters you can tell how much he despises talking to the press, and he gets through most questions through mumbling and disapproving glares. This casts fear into the media, who know that Bill is a man not to be messed with. He is much more animated on the sidelines, and quick to bark at underperforming players and officials. He famously chased a replacement official who was running off the field, grabbed him by the arm and let him have it after a last second loss. His mean look, hate for the media and vocal tirades make him a much feared coach by everyone in the league, but also because of his impressive record which speaks for itself. Bill is a five-time Super bowl Champion (three as head coach, two as assistant) and has taken the Coach of the Year award home three times.

7 7. Brian Clough

The stories of Brian Clough are legendary in the world of soccer, and this was certainly a manager that you did not want to cross. There are countless tales of both physical and verbal altercations that Clough got in with just about everyone, all of which can easily be found online. Perhaps the most famous though was when he floored Roy Keane in the dressing room after a costly error. He asked Keane (an intimidating player/coach in his own right) if he had ever been hit really hard before, and followed up with “you have now” after leaving Keane doubled over on the floor. Despite all this, Clough was much loved by those that knew him, and Roy Keane states that he was a better manager than Fergie and was a very warm and genuine person, as long as you were in his good books that is.

6 6. Earl Weaver

If anyone knew how to get ejected from a game, it was Earl Weaver. He would frequently unleash hell on umpires and was famous for his explosive temper, which made him a notorious and terrifying coach. Weaver’s trademark would be to turn his cap so that it faced backwards, as this would allow him to get into umpires faces without touching them. It would not just be verbal tirades that he would go on though; he would often kick or throw dirt at umpires, throw his hat to the ground and take it out on any inanimate object he could find. Earl was ejected nearly 100 times in his time as manager and must have caused nightmares for umpires, but he is now fondly remembered as a fantastic character in the game.

5 5. Gregg Popovich

Popovich’s military background has a clear impact on the way in which he manages his San Antonio Spurs, who perform like a well oiled machine. You will often see him barking at his players (including his stars) or giving them a cold stare as they walk past him to the bench, he is also often seen chasing after referees and he has become famous for his dry, blunt interviews with nervous reporters (who are only allowed to ask him two questions and often will get one-word replies). His approach clearly works for him as the Spurs play the best basketball in the league and have won five NBA titles in his reign, and he has taken home the Coach of the Year award three times. His players love to play for him and deep down he cares about each one, and we have seen a number of players blossom under his (stern) guidance.

4 4. John Tortorella

John Tortorella is not one to hold back his feelings or censor his words, as you will often see in his fantastic, expletive filled interviews and press conferences. Reporters will not get friendly answers to any questions that he does not want to answer, and he is quick to insult those with stupid questions. It is not just reporters that feel Tortorella’s wrath however, who has also openly criticised his players, thrown water bottles at opposing fans and chased after coaches down the tunnel into the dressing room to give them a piece of his mind.

3 3. Sir Alex Ferguson

There are not many coaches or managers in sports that are more intimidating than Fergie was. Not only did he possess a stare which could turn to stone, he was also famous for “the hairdryer treatment”, where he shouted so loudly at his players that it felt like they had a hairdryer in their face. There is also the legendary story of Ferguson kicking a boot at golden boy Beckham, leaving him with a cut above his eye. His post match interviews were often something to behold, leaving many reporters a trembling mess after asking a stupid question. A large part of what made Fergie so intimidating to everyone was his incredible knowledge and experience, as not many can say they have won as much as he did during his time as manager. This also meant that (most) who played under him have nothing but praise for his approach.

2 2. Tom Coughlin

Colonel Coughlin is a disciplinarian and  players don't want to get on his wrong side. He is famous for screaming at the top of his lungs and barking orders at his players, and if you are four minutes early for a meeting then you are late and will be punished. His methods may not be fun and players may feel like children playing under him, but he has proven that his methods work as he is a three-time Super Bowl Champion (once as assistant and twice as head coach). He has mellowed out over the years, but people are more than wary of this coach. Just ask Tiki Barber.

1 1. Lou Piniella

Angry. This is the first and best word to use when talking about Lou Piniella, and it didn't take much to get his blood boiling, and when he got angry he was going to take it out on someone or something. You always knew once you saw him leave the dugout that something special was about to happen, whether it was him throwing his hat on the floor in disgust as he chews an umpire’s ear off, spitting, kicking dirt at umpires or even picking up first base and throwing it into the outfield. This would of course always end in an ejection and provide a great source of entertainment for fans, but for umpires ‘Sweet Lou’ was a terrifying manager. Players were not safe from his wrath either, who he would often chastise and there is even footage of a clubhouse brawl between himself and Rob Dibble.