I don't know the context of these teams and their histories, nor the friendship between batter and pitcher, but I think I'm going to disagree with the majority here. Making it to the state championships is a often a big accomplishment and that's a time for a team to be celebrating together and presumably a pitcher is, or should be, a big part of that camaraderie.
If it was me, I think I go to my teammates first and greet my friend on the other side later, particularly since it was a six- or seven-run spread — it wasn't like the strikeout was going to shatter the kid that lost, and I'm sure he has teammates of his own that could pick him up. I'm thinking the batter would have understood all too well the contributions his friend made to his team and would not have thought any less of him for celebrating his win.