|Ring name(s)||Captain O|
Jūdō O</br>Hulk Ogan
|Real name||Ogawa Naoya|
|Nickname(s)||Bōsō-ō (暴走王) (Reckless King)|
|Billed height||193 cm (6 ft 4 in)|
|Billed weight||115 kg (250 lb; 18.1 st)|
Ogawa Naoya (小川 直也) is a Japanese former world jūdō champion, Olympic silver medalist, professional wrestler and mixed martial artist. He won a total of seven medals at the All-Japan Judo Championships (second only behind Yamashita Yasuhiro), and a set a record of seven medals at the World Jūdō Championships (tied with Robert van de Walle). He holds 5-dan in jūdō.
In professional wrestling, Ogawa was two-time NWA World Heavyweight Champion.
Ogawa Naoya first started in jūdō in his high school years. He continued on in college attending Meiji University in 1986. In his first year as a college student, he won the All Japan championship. In his second year at school he became a world freeclass champion, youngest in the history of jūdō at the time. He would go on to win many more championships before graduating from the College of Business Administration at Meiji University.
Ogawa was Silver medalist in jūdō of 1992 Summer Olympics, and placed fifth at the 1996 Summer Olympics.
In 2006, he opened Ogawa Dōjō in Chigasaki, Kanagawa.
In 1997 he was recruited by Antonio Inoki and was sent to train with Sayama Satoru in the newly-founded Universal Fighting-arts Organization. In his debut match, Ogawa defeated then-IWGP Heavyweight Champion Hashimoto Shin'ya with a sleeper hold in a non-title match on 1997/04/12 at the Tokyo Dome wrestling with New Japan Pro-Wrestling. A month later, on 5/3, Ogawa lost to Hashimoto after receiving a kick into his head, which became Ogawa's only loss to Hashimoto. His slump continued as Ogawa lost to Great Muta on 1997/08/10 at New Japan's Nagoya Dome card. He also lost in the final of the tournament to determine Inoki's opponent in his retirement match, against Don Frye on 1998/04/04 at Tokyo Dome.
To overcome his slump, Ogawa went onto a special diet and training and made a transition from a jūdō-based competitor to a mixed martial artist.
Ogawa's most famous match took place during a New Japan card on 1999/01/04 at Tokyo Dome when he made MMA-like offenses against Hashimoto. The match ended a s a no-contest after 6 minutes and 58 seconds. Ogawa grabbed a mic and said to the audience, "New Japan fans, please wake up!". The match was followed by a big brawl between New Japan and UFO competitors. Ogawa's status as a Bōsō-ō (暴走王) (Reckless King) went up.
On 1999/03/14, Ogawa won the NWA World Heavyweight Championship from Dan Severn in Yokohama. Ogawa lost the title to Gary Steele in a three-way match that also involved Brian Anthony on 1999/09/25. Ogawa won the title back on 1999/10/02.
Ogawa defended the NWA title against Hashimoto at Tokyo Dome on 1999/10/11. He again defeated Hashimoto via KO with the stipulation that Hashimoto would retire if he lost.
Hashimoto returned to the ring after six months but soon left New Japan to start Pro-Wrestling ZERO-ONE on 2000/01/25. Ogawa also started appearing on ZERO-ONE cards, mainly teaming with his rival Hashimoto.
Ogawa also continued to use his jūdō skills in PRIDE where he holds victories over Gary Goodridge, Stefan Leko, and American olympic silver medalist Matt Ghaffari. After seven wins in mixed martial arts, Ogawa faced PRIDE heavyweight champion Fedor Emelianenko, and suffered his first career loss by first round armbar. Ogawa retired from mixed martial arts after falling to fellow Japanese jūdōka, and rival Yoshida Hidehiko by an armbar in a highly anticipated MMA bout at PRIDE Shockwave 2005.  Ogawa and Yoshida were both paid $2 million USD which remains one the most expensive fight in MMA history.
- NWA World Heavyweight Championship (2 times)
- NWA Intercontinental Tag Team Championship (2 times)
- ZERO-ONE United States Heavyweight Championship
- Topic Award (1997)
- Fighting Spirit Award (1999)