Magic Diamond

Summer vacation has begun, and Malachi, Elizajane, Noah, and Elias are bored out of their minds. Playing pig pile doesn't help. Neither does banging one's face on the grass. What to do, what to do?
The kids decide to go downtown to see what they can see. They wander past the old drugstore, where Elizajane remembers something about sodas and It's a Wonderful Life. In a heartbeat she is gone, bolting around the corner to the back of the old building, where she finds a way inside.
The drugstore served some interesting characters over the years, and to everyone's surprise, one of them enters-through the locked metal front door! This old gentleman chats with the kids and tells them how there was once, long ago, a ball field right outside the back door.

After drinking a second "sarsaparilla courage," the old man shows them out the back door, where an incredible surprise awaits. Not only is the old ball park still there, but some of the old ball players are chucking the horsehide around, and one of them looks like Babe Ruth?
The kids are invited to join the game, but how do you play as a kid against the best players in baseball history?