Not bad. I would highly recommend also learning to shoot on a more manual setting, shutter priority is often good but learn how to shoot on both shutter and aperture priority as it is very lens-dependent. The reason why I say that is initially, based on the title alone, I figured you were going to ask people whether or not this mode is good for sports photgraphy. My short answer would have been no as it is nothing more than a setting that is intended to use under ideal conditions. Since that's cleraly not what your post is and you didn't ask I'm going to shut my mouth.
About the pictures.
This One is nice, seems sharp enough etc etc but I would have liked to have the pitcher a little more over to the right of the frame. Let the eye have some desire to move with the pitch...if it were released that is.
Personally
this is one of my favorites. The only thing lacking is the fact that I would love to have been on the other side to see faces and expressions and such. I'm using it as my wallpaper right now actually.
Hope you don't mind...if you do I'll tell you I'll dump the image and never use it again and you'll just have to trust me on that one.