Tamura made his debut in PRIDE Fighting Championships in a title fight against Wanderlei Silva for the PRIDE Middleweight Championship. Silva blocked Tamura's takedowns and attacked him with hard punches and a knee to the face. In one instance, Tamura landed a punch which stunned Wanderlei, but it was short-lived, and the Brazilian fighter recovered and continued with the brutal ground and pound, bloodying Kiyoshi's face. The second round saw the same action, with Silva counterstriking with a right hook which knocked out Tamura for the win.