How to foster a healthy winning attitude

I'm fairly new to the world of sports with my son who is an avid wrestler at only 11 y/o. I've been around wrestling the majority of my life, but it involved my brother and now it is my son. My son has been wrestling since he was 5 y/o and always has a winning season. Last year he won the Champion titile at our state's state games. This year the state games will be coming up again in another month and he is already starting to feel the pressure of matching his title again this year. I know this can be a good pressure for him, but at this age I don't want it to become so overwhelming that is consumes his every thought. How do I help make a balance. Of course I want him to win and give him encouragement in that direction, but we also don't want him to feel it is the end of the world if he doesn't win the same title this year. How do you facilitate a winning attitude, but also balance that? I don't want to sound like I don't have faith in his ability to go all the way. I was never an athletic person, so don't know the mental piece that I know is so important. Any suggestions would be helpful. I want to use sports as a way to keep my son involved, active, fit, healthy - I didn't expect this outcome of him becoming so competitive so quickly.