When Luis joins his new baseball team, the Manatees, things seem pretty hopeless at first. Some of his new teammates-including ''loud and obnoxious'' home-run slugger Jimmie-are mean to him or to each other. His new coach doesn't tell the players everything to do like his old coach did. And some of the Manatees seem more interested in goofing off than in sportsmanship or working hard. Then Luis is surprisingly named captain of his new team, and he finds himself with a whole new set of problems. How will he get this odd-ball group of teammates to work together?