A blurry (or out of focus) image is a blurry image - unless done intentionally for effect. No matter how much you "want" the image to turn out - it ain't gonna happen.
Watch the tilted backgrounds - I struggle with this also. If you forget - fix them!
I'm not convinced that all of the blur here is from motion. I would suggest that you practice two skills:
- proper holding/cradling of the camera and lens (monopods help, but I personally hate them).
- rolling your finger or some other technique to avoid "stabbing" at the shutter release to avoid introducing blur.
(Technique comes with practice - in sports shooting you are often reacting and getting caught up in the action and start to forget these things as you shoot. You don't have time to think about it while shooting like you do with static shots. I have to remind myself, too).
Kneel. The younger the player, the more important this is. It is a better perspective - trust me. I shoot less than 5% of my images standing up. This can be interpreted as personal preference.
(If you brace your left elbow on your left knee while kneeling - you can accomplish some of both of the past two tips - better bracing and perspective...)
You are up against tough odds without a 2.8 or faster lens for twilight or night shooting. I know, I tried it too. Even then - there are some diamonds that it just ain't gonna happen without the newest full frame cameras that can "see and shoot in the dark" - there just isn't enough light from many of the crappy lights on any (but even less on many municipal) diamonds. [After looking at the EXIF data on Flickr, I see that you did shoot with a pretty capable body and lens - although I don't really know much about the high ISO noise performance of the 50D.]
I had to invest some time to develop a workflow and techniques to adjust for high ISO/high noise shooting an PP techniques. Even then it is tough to shoot under these conditions without some practice. The higher the ISO, the more critical it is to get proper exposure.
Anticipation is a big helper! I started by trying to "shoot the whole game". I eventually found that I got better shots by focusing on little parts of the game and actually "thinking" about the shot rather than just reacting all the time. If you expect action at home plate, then focus on home plate and forget what's going on at 2nd base. I may bring home fewer but generally better shots. My strategy:
a. pick the best action area during action times (a runner at third is a good time to focus on home plate for a potential big play or a fast runner at 1st may mean good sliding shots during a steal at 2nd base...
b. focus on individual players for candid shots during "low action" periods - example: shoot tight on the short stop and third baseman when there are no base runners.
c. Don't stop shooting after the play - sometimes the best expressions and little moments happen "just after" the play.
d. Shoot during warm ups - really. You can generally focus on one player at a time and you already know here the "play" is gonna happen. Often the final shot looks like game action.
e. It is much easier to shoot if you don't have a vested interest in the game. I forget all of these tips sometimes when my daughter is playing. Often I find myself watching a great play and not shooting a great play - much to my own chagrin!
The images (in general) lack "pop" IMHO. They are washed out a little. I intentionally shoot this way and fix them in PP to help avoid blown highlights. This is harder to do with jpgs (I shoot raw), but I think you can see a little improvement with this example. (More than happy to delete, if this bothers you).

Actions:
- Straighten
- Crop a little tighter
- A little high pass sharpening
- Increased contrast
- Increased the color (protected skin tones).
GOOD LUCK!