OK, so they had their one warning already. Now, the teammate is about to tell their teammate they are shooting the wrong ball. Is it still sportsmanship? What will the other team say. "oh, yeah, it's cool, no worries" Obviously, it depends on team.
But, they could call a foul on someone that was acting with good sportsmanship, correct? Hence, why I don't believe it is good sportsmanship to tell your opponent they are making a mistake. See where I'm going with this
Should I tell my opponent when he is going to shoot an obvious scratch shot ? I mean, why would I let him foul because he does not now his tangent line