First let me emphasize that I am a dog lover! However, I don't think they belong at the ball park. I mean, it is too hot (especially for older dogs) unless you are going to sit with them in the shade all day. A feat that is almost impossible at many ball parks. Also, please note that the concrete, sidewalks, etc.. get very HOT on a dogs pads. I'd like to shoot people I see who ride their dogs around in the unlined bed of a pick up truck on a hot day!!!! Not only is it dangerous in the event of an accident, I consider it animal cruelty.
I am all for socializing dogs, but that is what family get togethers, obedience training, doggie daycare, and dog parks are for. A good old fashioned walk in the park in the am, before it gets hot, works too-I guarentee there will be other responsible dog owners there to socialize with.
I would say let them stay home in the nice air conditioned house where they will be safe and secure upon your return.
NEVER leave your dog tied up outside all day! Do people still do this!? I am apalled! >
If you can afford to play travel ball, you can afford to pay a neighbor to let your dog out for you when you are gone!