On March 31, 2005, Akebono made an appearance on SmackDown to accept the Big Show's challenge to a sumo match at WrestleMania 21. Akebono made his wrestling debut later that night, defeating jobber Eddie Vegas. At WrestleMania 21, Akebono defeated the Big Show with a koshinage, throwing him entirely out of the ring.
On July 1, Akebono made an appearance in a house show in Japan to help the Big Show during a match against Carlito after Carlito's bodyguard Matt Morgan had interfered. The next day, Akebono teamed with the Big Show to defeat Carlito and Morgan in a tag team match.