Kuniaki Kobayashi
When he returned to Japan, Hase wrestled for NJPW's junior heavyweight division, winning the IWGP Junior Heavyweight Championship twice. He defeated Kuniaki Kobayashi on December 27, 1987 and held it until May 27, 1988, losing the title to Owen Hart. His second reign began by defeating Shiro Koshinaka on March 16, 1989, and held it until May 25, 1989, losing it to Jyushin Liger. In June 1989, Hase and Takayuki Iizuka went to the Soviet Union to be trained in sambo, where he learned one of his signature moves, the uranage. He would also become one of the only wrestlers, Japanese or American, to successfully graduate from the junior heavyweight to heavyweight class.