It has been said that tennis is 10 percent physical and 90 percent mental, as tennis players have nothing but themselves and their own thoughts to keep them company during a match. After all, tennis is one of the few purely individual sports in existence -- you, and only you, are responsible for how well you can handle the many different factors of the game like pressure, the weather or your opponent’s antics. Because of this, there are many things unique to the sport that tennis players find themselves having to deal with that, both good and bad, other athletes don’t. Here are 11 things that stand out in particular.

1. You have to drag your stuff onto the court for every match.

Even the top players in the world have to carry their bags, water bottles and other gear by themselves onto the courts of the biggest tournaments like Wimbledon and the U.S. Open. This isn't necessarily a bad thing; however, a lot of players feel it gives them a certain amount of security and comfort, as they know exactly where their stuff is and how much it's being tampered. Still, it is a bit of an odd sight to see tennis stars lugging their heavy tennis bags around before a match.

2. Tennis courts can come in many different surfaces.

Those surfaces are hard (most popular in the U.S.), clay (the standard in Europe and South America), grass (primarily England) or carpet (mostly used for recreational matches).If you play regularly, especially as a professional, you have to take a certain amount of time to adjust to a new surface since the ball bounces very differently on each surface. There's also a major difference in whether a match is played indoors or outdoors.

3. The scoring makes no sense.

It's probably written down somewhere why the score can go from zero (love) to 15 after one point, then straight to 30, then to 40, but it's a bizarre rule nonetheless (especially given that tiebreakers are played with normal 1, 2, 3 scoring). For better or worse, however, it has become an integral part of the sport, so there's definitely no changing it anytime soon.

4. Momentum swings are deadly and can happen at any point.

You could be playing the match of your life, be serving with triple match point and still lose the match if the momentum were to suddenly swing away from you. It's not uncommon to see a better player fall to a weaker player simply because the weaker player managed to piece together six or seven points in a row when it mattered. It's true that every sport has this type of phenomena to some extent, but momentum swings are unique to tennis in that there are no teammates to bail out the lagging player. It doesn’t matter how good you are, because in the end you are responsible for not letting your game dip and allowing an easy match slip away from you.

5. In some matches you can't consult or talk to your coach.

Junior players and professional women players can ask their coaches to come on to the court at certain points, but in professional men's tennis players are forbidden from conversing with their coaches. Whether or not this rule should be overturned or not is an ongoing debate in the tennis community, but it's fair to say that men's tennis is one of the loneliest sports in the world.

6. Smashing a racket can seem like a really good idea sometimes.

Fortunately for basketball players, you can't destroy a basketball like you can a tennis racket. Frustration is a key part of any tennis match - no player walks off after losing without feeling a little bit of it. Yet the frustration of blowing a lead or losing badly to a substantially weaker player can build rapidly, at which point one's thoughts become clouded with negativity. At that point, yelling, tossing a racket or even smashing it to smithereens can happen without the player truly realizing it until it's already happened. The best players are those who can clear their heads when it matters and move on to the next point (and though it's not recommended, sometimes smashing a racket can help a player do that).

7. You know you need new shoes when...

Your toes literally dig holes through the front of your shoes (and sometimes socks too), which is a common occurrence for tennis players everywhere. I speak from personal experience when I say that nothing feels quite as strange as when you're playing and your bare toe hits the rugged surface of the court.

8. You've accepted that you'll always have a farmer's tan.

For better or for worse, that's just a part of the game.

9. Left-handed players are a nightmare.

You've trained all your life to pound the ball to your opponent's backhand, only to find yourself now hitting to his or her forehand. There's a reason Spanish legend Rafael Nadal has a major head-to-head edge over Swiss great Roger Federer - Federer's one-handed backhand isn't completely effective in dealing with Nadal's high-spinning forehand.

10. Players who only serve with only one ball in their pocket should be banned.

You hit your first serve and miss. It takes about .5 seconds to reach into your pocket and get another ball, but it takes several seconds longer to walk behind you and find another ball lying around to serve with. Unless you're wearing shorts or pants that don't have pockets, there are a very limited number of plausible excuses you can make for committing this grievous sin.

11. Unless you're a professional, you have to make your own calls.

By far the biggest source of tension between players in the sport of tennis, balls that land close to or on the line are called per the discretion of the player on the side of the court that the ball landed. There exist computers (dubbed "Hawkeye") that can pinpoint the exact point a ball lands, but these only exist in the top tournaments in the world. Therefore, no matter how ugly it gets, players must come to some sort of understanding or agreement on a contested call.

The previously mentioned "ugly" side of this happened to me once when I played a junior match a few years ago. My opponent hit an approach shot and came to the net, forcing me to hit a lob over him. My ball clearly landed a foot inside the line, yet my opponent (probably thinking he was blocking my view of the ball) called it out and went to serve the next point. When I began to protest, he responded with, "Please don't talk to me while I'm serving." Despite his unfair calling I eventually won the match, but it was definitely a hard way of learning this rule. Fortunately, the majority of the tennis community plays fairly and by the rules, preferring to have fun than to cheat. At the end of the day tennis is just a game.