It's only normal for athletes to feel anxiety in a competition, which is mainly triggered by an overwhelming fear of losing the game.
As suggested above, it's the fear of losing that causes anxiety in sports. That's the main cause. But other factors are also to be blamed. You may think you are unable to cope with uncertainty in a game. Or you believe you need to present a perfect performance. Some young athletes may freak out when they're strongly affected by anxiety and don't know how to cope with it. If an athlete thinks he or she is the only one who experiences anxiety during a game, his or her anxiety will worsen.
Keyword: anxiety sport