Last year my DD was out for over 3 months with a stress fracture in her back. 13U team, highly competitive. She didn't miss a thing, including an out of town tournament 6 hours away. At the tournament, it was her job to run the video camera and to try to pick up tendencies from the opposing pitcher. She attended practices. She even met with the coach for her individual workouts. She couldn't swing a bat or throw a ball, but she could do vision training on a computer. And she watched hours of tape of college pitchers (coach is also a D2 assistant colleege coach) where she got quite adept at picking pitches based on how the pitcher was holding the ball, where her hands were, etc. So... short answer is YES, I would expect/demand that an injured player attend practices and games (obviously depending on the severity of the injury).