Rikkai-Dai Trinity is Yukimura, Sanada and Yanagi. They won Nationals two years in a row (once as freshmen, once as juniors) and now they're competing for their third title. Except - cue the DRAMA! - Yukimura has contracted some sort of degenerative muscle disease, so he can't play, and his team without his calm, pretty-boy buchou-like guidance, falls under the influence of the psychos. i.e. Kirihara and Sanada, and potentially Niou and Marui. Sanada and Yanagi are actually in the manga, briefly, when they mention Rikkai-Dai - the guy in the baseball cap with the scary eyebrows and the guy whose eyes are perpetually closed, but who looks vaguely more asian than Fuji.

Fudomine OT3 is Tachibana/Kamio/Shinji of course!