It is a shame that happened, but i have to say... i dont respect that self-destructive action of his, i understand loving the game and pouring himself on it, but he is too young to be already overworking himself to that level and not taking early precautions. If what Suu-chan said really is the truth this injury may hinder his whole career.
I can blame the couch too, taking responsibility for his teen players healthy isnt even a topic for consideration, it is his duty to see that these kids dont injury themselves even if they themselves dont see those injuries happening, more so when they are playing at already such high-level competition.