Shin Tennis no Oujisama

After the national tournament, Ryouma Echizen and 49 elite middle school players are invited to Japan's U-17 training camp, a place previously reserved for high school athletes. The older players greet them with open hostility, but the greater surprise is the camp's ruthless system: 16 courts rank everyone by strength, and daily matches can send a player sharply upward or down.

The middle schoolers are then asked to form pairs, only to learn that each pair must fight one another rather than play together, with the loser being sent away. To reach national-team level, Ryouma and his former rivals must put friendships aside and face opponents far stronger than anything they encountered in school tournaments.