Let me repeat that because it’s so important: WHEN YOU GET ANGRY, YOU GIVE AWAY YOUR POWER.  And most of the time, the anger is misdirected and has little or nothing to do with the sporting event. For example, let’s assume that Serena Williams had an issue (argument?) with a friend the night before competing against Samantha Stosur in the US Open women’s final. Because she didn’t clear the issue with her friend, she erupted in anger at the chair umpire, just as she had done before, and also just as before, she was defeated. You often see this in other sports as well, such as when a defensive tackle in the NFL gets into an altercation with the offensive tackle on the other team, or an NBA basketball player gets into a fight with a member of the other team. These types of outbursts take the focus off winning and create baggage that affects performance. So the lesson to be learned is, never allow an issue to fester since it will never go away. It will only become more intense.  Issues must be addressed directly and resolved. Or at least, begin the process of resolving them.