My oldest was nationally ranked in swimming by the time he was 11 - he's 30 now, so that was a while ago. He won state in high school at free style sprints, and wound up lettering 4 years at USNA on their swim team (swam against Michael Phelps in one meet, Phelps destroyed him, but he took that in stride)
As a youngster, he had some natural talent, and he worked pretty hard at it. But there were a couple boys in other clubs in greater Houston who usually got the better of him. We were driving home from one of those disappointing meets when I told him "When you get in the pool at practice tomorrow, remember how much this hurts. Remember it the day after that and the day after that. Remind yourself every day how bad this feels, let that motivate you to do better at practice." That was 3 or 4 months before his 11th birthday. He was ranked by the time he turned 11.
Winning is awesome, but having played and coached basketball and baseball, having my own kids being uber competitive, it has been my observation that the intensely competitive kids can learn more by losing than they ever can by winning.
Congratulations to your boy, I wish him continued success. But teach him the lessons, if he hasn't already learned them, to work through defeat, to develop the sort of character necessary to overcome those inevitable setbacks.