After doing hard labor with a battery of Mexican sparring partners, Japanese Naoya Inoue finally capped his buildup for the 26 December unification super-bantamweight title clash with Filipino southpaw Marlon Tapales in Tokyo.

Inoue, nicknamed "Monster" owing to his devastating power on both hands, imported several big-hitting sparmates from Mexico knowing he has to be in tip-top shape.

At stake are Inoue's World Boxing Council and World Boxing Organization 122-lb straps and Tapales' World Boxing Association and International Boxing Federation belts.

The overwhelming betting favorite, Inoue is attempting to become an undisputed titleholder for the second time after becoming one at bantamweight (118 lbs).

Tapales, meanwhile, is bidding to become one and the first Filipino to pull it off, a feat not even the legendary Manny Pacquiao was able to do during his Hall of Fame career.

However, Tapales faces tremendous odds as he collides with a fighter with no known weaknesses and soft spots.

Still, Tapales oozes with confidence in this mega-bout taking place at the Ariake Arena.

"I feel great and I am not at all bothered by the odds. I trust what I have and I am going to show it on fight night," Tapales said from Baguio City, where he has been training since the first week of November.

Team Tapales leaves for Tokyo on Tuesday.