全国大赛后，网球王子们来到了高中生代表候补的合宿地，开始了一番新的未来。全国中学生们又一次向日本证实了他们的实力。那里高手如云，每日进行着魔鬼训练。高中生代表候补的合宿地是从1号场地编排到16号场地，实力越高的人就在越小的数字的场地训练。静待王子们是如何从U-17选拔候补的最底层爬到高中生合宿的顶端，并在这之后走向世界的舞台！

After a month abroad, the Foreign Expedition Team has returned to the Japan U-17 training camp. The group consists of 20 players, each with strength and technique that far surpasses those who occupy the camp's top court. In anticipation of the team's arrival, the coaches announce that 20 of the best players would be selected for further training. Tension begins to rise when only high school students are chosen to participate, but the middle school students challenge the players who possess the 11th to 20th positions to steal their places.

With the delayed appearance of the "Genius 10," the middle school students begin scheming among themselves to claim those spots as well. Unlikely pairings start to work together, combining their efforts to defeat the top 10 players of the country. It is a battle of wits, deception, and skill—all for the privilege of representing Japan at the U-17 World Cup.