"Coach, we're not going to charge out of the dugout to argue judgement calls, are we?" Something like that almost always settles them down a tad, and sometimes brings forth an apology, and lets you discuss whatever he's upset about calmly.
Then, "Coach, I called safe because I saw no tag." Nuff said. Or - if I called him out, "Coach, he tagged him on the ponytail. Get that kid to cut his hair and he's safe."
