World Victory Road confirmed that the Middleweight GP Series will start at Sengoku 5 on 28th September in Yoyogi National Gymnasium. Kazuhiro Nakamura drops his weight to participate in the Sengoku Middleweight GP. The other participants are Evangelista Cyborg from Chute Boxe, Siyar Bahadurzada who is SHOOTO Light Heavyweight Champion, and 2007 Strikeforce Middlweight Tournament winner Jorge Santiago.
Also confirmed was additional fight in Sengoku 5. Kazuo Takahashi faces Valentijn Overeem on 24th August.

SENGOKU 4
Date : August 24th, 2008
Place : Saitama Super Arena in Saitama, Japan
Fight : Takanori Gomi vs Bang Seung Hwan [Lightweight]
Makoto Takimoto vs Frank Trigg [Middleweight]
Peter Graham vs Moise Rimbon [Heavyweight]
Takahashi Kazuo vs Valentijn Overeem [Heavyweight]
Lightweight GP Series 2008 1st Round :
Satoru Kitaoka vs. Clay French
Eiji Mitsuoka vs. Rodrigo Damm
Kazunori Yokota vs. Bojan Kosednar
Mizuto Hirota vs. Ryan Schultz

SENGOKU 5
Date : September 28th, 2008
Place : Yoyogi National Gymnasium in Tokyo, Japan
Lightweight GP Series 2008 1st Round participants :
Kazuhiro Nakamura
Evangelista Cyborg
Siyar Bahadurzada
Jorge Santiago