I'm right there with you! Thankfully our baseball pants are grey but that only helps hide the very faint dirt stains a bit, not the grass. I usually use Tide and scrub it in, as well as doing it as soon as I can so it is a fairly fresh stain. Haven't had the chance to use my new stain stick on them yet (will tonight though) My oldest DS got upset that I was trying to clean his football pants..."it won't look like I've done anything!" So......
This just reminded me, have to wash a uniform for tonight!