Kazuhiro Nakamura, Jorge Santiago, Siyar Bahadurzada and Evangelista "Cyborg" Santos are entering the tournament for a chance to be crowned the "Sengoku" middleweight champion.
Nakamura (11-8), who was released by the UFC after two straight losses in the Octagon, will drop from light-heavyweight to middleweight to enter this tournament. The judoka returns to Japan for the first time since losing to Mauricio "Shogun" Rua at PRIDE Shockwave on New Year's Eve 2006.
Santiago (17-7) has already found success with another middleweight tournament, knocking out Sean Salmon and Trevor Prangley in one night to win the Strikeforce tournament championship in November 2007.
Bahadurzada (13-3-1) is the Shooto light-heavyweight champion and lost his sole "Sengoku" appearance in March to Kazuo Misaki, whom Bahadurzada and the rest of the participants will most likely be gunning for at the conclusion of the tournament.
Chute Boxe's "Cyborg" Santos (16-11) won at the first "Sengoku," tapping out Makoto Takimoto in the first round.
Four more participants will be announced to in the future to round out the first round.