A 12-year-old right-handed boy who pitches for his club and for his school team is brought in by his mother after a message from the club coach. Three weeks ago the coach took him off the mound: his pitches had lost speed and kept sailing high, and in his last two starts he asked to come out by the third inning — something he had never done before. He now plays first base, leaves his glove in the bag at practice until he is called, and has stopped playing catch with his younger brother. Asked what is wrong, he says "my arm" and will not be more specific. It has been creeping up for about six weeks, with no single day it started, no fall, no collision and no throw he remembers going wrong. He looks well, a little bored by the questions, and wants to know one thing: whether he can pitch in the end-of-season tournament in three weeks.