The Hiba Junior High team did not exist until around the same time as the start of the series. Though there was a group of students who had tried to make one previously, they were rejected; officially, the rejection was on the grounds of having too few members, but it's heavily implied that it's also in part because the group was a crowd of deliquents. (In their flashback, we see them skipping class almost immediately.) The addition of Shiina Tsubasa gave them their necessary fifth member, as well as a strong leader and a well-liked representative, and tipped the scales in favor of the team's creation.
Their team has an intimidating defense with a strict formation that even shut down the powerhouse forward Tenjou Ryoichi with apparent ease.