On December 6 , WWE filed a motion for a temporary restraining order to prevent Lesnar from continuing to work with NJPW , but the court did not grant it . Following that , he had two non @-@ title victories against Manabu Nakanishi and Yuji Nagata . Lesnar successfully defended his championship on January 4 , 2006 , against former champion Shinsuke Nakamura . On January 13 , WWE once again filed an injunction against Lesnar to stop him from defending the IWGP Heavyweight Championship which was also not enforced as he went on to retain his championship against former Sumo Wrestling Grand Champion Akebono on March 19 , at the Sumo Hall . Lesnar had another successful title defense against Giant Bernard on May 3 , 2006 . This was the first American vs. American title match in NJPW since Vader vs. Stan Hansen in 1990 .