This is a subject which I have been discussing with my students a lot recently, due to a lot of recent competitions. I think it can be almost as important as the physical side of things, but is often neglected by people as it's something they just don't think about.
Now I'm not talking about mental preparation for fights. I know some people spend a lot of time on that but I find it quite difficult to understand. I never step on the mat without thinking I am going to win and have never felt doubts about my own ability before a competition. What I am talking about is the mental ebb and flow during a fight. So many times I have seen students win fights, or lose very close fights (or even fights they have overall dominated) and they come off the mat with the feeling that they performed poorly or almost lost when in reality they won easily.
Why does this happen? First, I think adrenaline is a big factor, it numbs the mind and means that memories of a fight can be very foggy... I have had fights which I couldn't remember until watching a video! There is also a natural tendency for most people to be critical/negative of themselves and, lastly, people often only think about the last thing which happened during a fight.
What does this mean? Well, there are two fights going on during a match... the physical fight and the mental fight, and they are both vitally important. I have seen people winning fights easily who then make one mistake and suddenly panic, causing them to lose the fight. Or people who have been getting smashed but are so strong mentally they never give up and manage to win by submission.
So how does this all relate to aspects of a fight? The easiest way to explain is looking at the situations this stuff most often applies...
1. If you're in a bad spot and you escape then realise you are winning the fight at that point. Ok, you might be losing on points, but the ebb and flow of the fight is going in your favour, so when you get back to a good or neutral position don't stop, keep moving forward, it's the best time to attack. Your opponent has just lost a strong position and could be disheartened. The same for escaping a submission attempt... it may have been their best attack, they might have been sure they would submit you and now you've escaped... attack!
2. The opposite of the first point; you had a strong position and your opponent escaped. Relax, you got ahead of them once so can do it again. Don't freak out and do something silly, just control the position they have escaped to and go back to attacking.
3. You get reversed from side control. This is a classic that I've seen totally change a fight. Not only were you in a good position which your opponent has escaped, they've put you straight into a bad position. You need to stay calm, if you freak out and desperately try to escape you may end up in an even worse position or get submitted. This is another reason to learn the rules and points system... side control reversal, or being put in side control from top turtle doesn't score your opponent anything. In these circumstances you need to be strong enough mentally to relax, defend and take your time, your chance to escape will come.
4. The fight starts and you end up exactly where you didn't want to be... they took you down, or they pulled guard first. So what? You can panic or you can back yourself to win the fight. Stuff goes wrong in a fight and you have to be ready for it.
There are obviously other ways that show how mental strength during a fight is important, but from my experience they are the most common. Just like learning techniques I believe you can learn methods to improve your mental game. First of, as mentioned earlier, learn the rules and points system back to front... if you know exactly what is happening in a fight it makes it much easier to cope with adverse situations. Also, try to have someone coaching you from the sidelines they can help you by telling you the points and time. Think more deeply about what is happening when you're training, don't just live totally in the moment. Try to think about the overall round and what is happening at each point; you might have been getting smashed for 4 minutes but if you then get the upper hand... go, go, go, push forward hard and work to get the submission or enough points to turn it around. If you're winning the fight at a specific point, whatever came before doesn't matter.
Fight hard, be strong mentally and never give up no matter what has happened!!