Baseball pants are another uniform essential. They're often made of polyester and the same color as the jersey and come down past the calf, but above the ankle. Players can choose to have their hem open or closed, whatever is most comfortable. They're often a neutral color at the beginning of the game, but end up with plenty of grass and dirt stains. Often held up by a belt, baseball pants should fit tight, but still be breathable to allow players to run comfortably. Since the pants bear the brunt of slides and dives, pants usually come with extra fabric around the knee and back end area for support.