"Sure, this is a totally new experience for me so I'm worried about everything," Akebono said Wednesday after a training session in Tokyo. "In sumo, you pretty much know your opponents' strengths because you practice against them. In the case of Sapp, I have no idea how strong he is and no idea what to expect."

Akebono, a Hawai'i native who was the first foreigner to reach sumo's highest rank of grand champion (yokozuna), severed all ties with Japan's ancient sport earlier this month in order to take up a career in K-1, a brutal sport that combines elements of kickboxing, karate and tae kwan do.

He is scheduled to take on Sapp on Dec. 31 at Nagoya Dome.

Sporting dyed hair and an earring, Akebono said he tried boxing once as a kid but things didn't work out.

"When I was 11 years old, I tried it," said Akebono, a Kaiser High School alum. "I got knocked out by the coach and quit."

The 6-foot-9, 484-pound Akebono will rely on his size and has been working on his punches for the bout against Sapp, who stands 6 foot 7 and weighs 350 pounds.

Akebono's trainer Steve Kalakoda, who has worked with K-1 fighter Mike Bernardo and several boxing heavyweights, said the soft-spoken Akebono has been working on a left hook and will have some things working in his favor when he steps into the ring.

"Akebono has enormous power," said Kalakoda. "I've worked with several heavyweights over the years and I can tell you he has enormous power."

In Wednesday's sparring session, Akebono landed a few solid lefts but was slow in moving about the ring. The gimpy knees that forced him to retire from sumo two years ago will be vulnerable in any sport that allows kicking.

"I've been training very hard," said Akebono. "I feel a lot lighter than when I was in sumo."

In sumo, Akebono relied on a thrusting and lunging technique that he used to overwhelm his opponents on his way to winning 11 Emperor's Cups.

Sapp, nicknamed "The Beast," has made a name for himself in Japan through K-1 since giving up on his career with the Minnesota Vikings. While he's enjoyed some success in the ring, he is 4-3 and lost his last bout. Many in the sport feel he is past his prime.