Back to school and coach's church
Though they used a school bus, the trip was not sponsored by Breckinridge County High School in Louisville, Kentucky (another coach paid for the gas). The Louisville Courier Journal reported  that even the school's superintendent, a member of the church, was there.
It's unclear what the students knew about the trip, but that hardly matters. I agree with David Friedman, general counsel for the American Civil Liberties Union of Kentucky: "Coaches have great power and persuasion by virtue of their position, and they have to stay neutral." Share your opinion on the separation of church and state. 
But from a religious standpoint, I'm not sure the coach's tactic was even that good. What good are you doing for your players by leading them to a spontaneous, unplanned Baptism? It would seem to me that inviting them to participate in a youth group, Bible study, or catechesis would be more effective.
Each of these still would cross the church/state divide for me, but I do think that people of faith can use that "great power and persuasion" as a coach to lead by example.
The other interesting question here is, at what age can you make a religious decision on your own? The superintendent said she would have gotten permission slips for 7- or 8-year-olds but didn't need to for 16- and 17-year-olds. The pastor said he generally baptizes people 18 and up, but doesn't ask for ID.
Meanwhile one angry parent said she (a Baptist) and her husband (a Catholic) were waiting until their son was 18 to let him make a decision on religion. Perhaps this is just the strategy that left their son looking up to their coach, and not them, for religious guidance.
And yes, that statue is real, from Catholicshopper.com !