Ishii started Judo under the guidance of his father when he was in fifth grade of elementary school. He attended Kokushikan High School and then Kokushikan University in the Department of Physical Education.[3]
On 30 April 2011 Ishii returned to Judo to compete in the United States Championship in the open division; he won all the matches, securing the gold medal.[7]
Mixed martial arts career
Early career
After winning the gold medal, Ishii expressed his wishes to apply his talents in the sport of mixed martial arts (MMA) to the dismay of the Japanese Judo Federation.[8] Ishii originally confirmed that he signed a contract with Japanese MMA promotion Fighting and Entertainment Group (FEG) and was rumored to debut in early 2009 in their fight series, DREAM.[9]
Japanese newspaper Sports Nippon then reported that Ishii would make his ring debut on December 31, 2009, at the annual K-1 Premium Dynamite!! event at the Saitama Super Arena. However, Ishii announced that he rejected FEG's offer, and was planning to pursue his MMA career in the US' Ultimate Fighting Championship (UFC). He headed to Florida where he trained with one of MMA's top camps American Top Team.[10]
On June 1, 2009, Ishii announced he would join Japanese MMA organization World Victory Road.[11] He officially signed with the organization at a public signing event on June 4, 2009.[12] On September 14, 2009, it was announced that Ishii would make his MMA debut against fellow Olympian judo gold medalist Hidehiko Yoshida.[13] Although the fight was originally to take place at World Victory Road's New Year show on December 31, when that event was cancelled, the fight was moved to DREAM's Dynamite!! 2009 card on New Year's Eve as a co-promoted show.[14] Ishii, who was a large favorite in the fight, was dominated in the first round by the more-experienced Yoshida, taking many strikes including a right overhand that staggered the newcomer, along with a series of knees and uppercuts from the clinch. Ishii, however, came back with a more competitive second round, but took a point deduction after illegally kneeing Yoshida in the groin. Ishii continued to find his range in the third round with punches, but ultimately lost via unanimous decision.[15]
For his second fight, Ishii faced New Zealand heavyweight kickboxing champion Tafa "Thumper" Misipati on May 15, 2010, in Auckland, New Zealand. The fight was the main event at the ETK production X-plosion: New Zealand vs. Japan. Ishii won via submission (armbar) in the first round.[16]
In June 2010, Ishii caused controversy during an MMA exhibition match on the undercard of X-1 World Events: Nations Collide in Hawaii. After knocking down his opponent Myles Tynanes at the end of the first-round, Ishii failed to stop punching his downed foe despite the referee's attempts to halt the action. He was subsequently disqualified for his actions.[17]
Ishii then fought French kickboxing star Jérôme Le Banner in a mixed martial arts bout at the Dynamite!! 2010 New Year's Eve event.[22] He won the fight via unanimous decision.[23]
Ishii was scheduled to make his North America debut for Strikeforce at Strikeforce Challengers 15 against Scott Lighty, but a visa issue stemming from the recent earthquake and tsunami left him unable to leave Japan. Lorenz Larkin took his place in the fight.[24]
In April 2011, it was reported that Ishii would retire from MMA and return to judo. Surprisingly, he said that he plans to earn American citizenship and represent the US at the 2016 Summer Olympics.[25] However, he apparently decided against retiring from MMA as he went on to face former WEC Middleweight ChampionPaulo Filho at Amazon Forest Combat 1 on September 14, 2011, in his light heavyweight debut. The fight ended in a controversial draw, with journalists as well as the crowd agreeing that Ishii had won all three rounds.[26]
Satoshi Ishii next competed at Fight For Japan: Genki Desu Ka Omisoko 2011, where he met MMA legend Fedor Emelianenko.[27] He lost the fight via KO in the first round.[28]
Ishii then faced Kazuyuki Fujita on December 31, 2013, for the IGF Championship. He won via unanimous decision, became the first IGF Champion.[33]
Ishii defeated former UFC fighter Phil De Fries in a non-title bout via unanimous decision at IGF 1 on April 5, 2014, in a full pride rules match as the headline bout on the card.[34]
On August 23 at IGF 2, Despite being a heavy favorite due to his years and judo experience Ishii was defeated by UFC, Pride and K-1 veteran Mirko Cro Cop via doctor stoppage, losing the IGF Championship in the process.[35][36]
Ishii was expected to face PRIDE and Strikeforce veteran Sergei Kharitonov at M-1 Challenge 53: Battle in the Celestial Empire on November 11, 2014.[37] However, Ishii withdrew from the fight due to injury.[38]
Ishii faced Mirko Cro Cop in a rematch at December 31, 2014, for the IGF Championship.[39] Early reports had the rematch cancelled due to a rib injury sustained by Ishii.[40] However, in December 2014, it was reported that Ishii would be able to heal up in time to fight Cro Cop, and the rematch was official once again.[41] Ishii lost the fight via TKO at the end of the second round.[42]
After suffering back-to-back losses to Cro Cop, Ishii was scheduled to face Nick Rossborough at Inoki Genome Fight 3 on April 11, 2015. He won by a first-round submission.[43]
Ishii fought Will Penn in his final IGF appearance, at Inoki Genome Fight 4 on August 29, 2015.[44] He won the fight by a first-round submission.[45]
Rizin FF
In his debut for the Rizin promotion, Ishii faced Jiří Procházka on December 29, 2015, at Rizin Fighting Federation World (8-men) Tournament.[46] He lost the fight via knockout early in the first round. However there was some speculation about a possible fight fix, as a head kick thrown by Procházka appeared to be blocked by Ishii, but Ishii collapsed anyway and was finished off shortly after.[47]
Ishii made his North American MMA debut against Quinton Jackson on June 24, 2016, at Bellator 157.[48] He lost the fight via split decision. One judge scored the fight 29–28 to Ishii, while the other two judges scored it 29–28 and 30–27 for Jackson.[49]
Ishii was scheduled to face Muhammed Lawal at Bellator 169 on December 16, 2016. He lost the fight by unanimous decision.[50]
Following his third consecutive loss, Ishii was scheduled to face the long-time mixed martial arts veteran Heath Herring at Rizin 2017 in Yokohama: Sakura on April 16, 2017. He snapped his losing streak with a unanimous decision victory.[51]
European circuit
Ishii was scheduled to face Ivan Shtyrkov at RCC Boxing Promotions: Russia vs Japan on July 9, 2017. He lost the fight by a first-round technical knockout, as Shtyrkov floored the Olympian with a right straight.[52]
Ishii made his first and only Final Fight Championship appearance against Björn Schmiedeberg at Final Fight Championship 30 on October 21, 2017.[53] He won the fight by a first-round submission.[54]
Ishii was scheduled to face Rokas Stambrauskas at German MMMA Championship 17 on October 13, 2018. He won the fight by a first-round submission.[55]
SBC Heavyweight champion
Ishii fought for the Serbian Battle Championship heavyweight title in his debut for the organization, against Tony Lopez at SBC 19 on December 1, 2018.[56] He won the fight by a first-round submission.
Ishii made his first SBC heavyweight title defense against Rodrigo Carlos at Serbian Battle Championship 20 on February 16, 2019.[57] He won the fight by a first-round technical knockout.[58]
Ishii challenged Cally Gibrainn de Oliveira for the HEAT Heavyweight Championship at HEAT 44 on March 2, 2019. He claimed the title via second-round submission.[59]
Ishii was scheduled to face the former KSW champion Fernando Rodrigues at KSW 47: The X-Warriors on March 23, 2019.[60] He won the fight by split decision.[61]
Professional Fighters League
On January 1, 2019, Ishii revealed that he had signed a contract with Professional Fighters League, and he took part in the second heavyweight regular season.[2]
Ishii faced Zeke Tuinei Wily at PFL 3 on June 6, 2019, in his promotional debut. He won the fight by split decision.[62]
Ishii faced Denis Goltsov in the 2019 heavyweight quarterfinal bout at PFL 9 on October 31, 2019. He lost the fight by majority decision.[65]
Second run on European circuit
Ishii faced Jake Heun at Rizin 20 on December 31, 2019.[66] He lost the fight via first-round knockout.
As his first HEAT title defense, Ishii faced Cleber Souza at HEAT 46 on January 19, 2020. He retained the title via first-round submission.[67]
Ishii next faced Stuart Austin for the inaugural EMC Heavyweight Championship at EMC 5 on September 5, 2020.[68] Ishii lost a controversial unanimous decision, to which his team decided to appeal.[69]
Ishii faced Pietro Cappelli at EMC 7 on July 3, 2021. He won the fight by a first-round submission.[70]
Ishii was scheduled to face Daniel Spohn at HEAT 50 on May 7, 2022.[71] However, the bout was scrapped after Spohn tested positive for coronavirus.[72] Ishii was instead booked to face Charlie Milner at FNC 6 on June 17, 2022.[73] He won the fight by a first-round knockout.[74]
Return to Professional Fighter's League
On June 6, 2023, Ishii announced that he had signed a new contract with PFL in order to make his return to the promotion.[75] He competed against Danilo Marques at PFL 8 on August 18, 2023.[76] He lost the fight by unanimous decision.[77]
On March 3, 2024, Ishii announced his retirement from MMA competition.[78][79]
Kickboxing career
On August 3, 2021, it was announced that Ishii had signed with K-1.[80] He was scheduled to make his kickboxing debut against the one-time cruiserweight title challenger Ryo Aitaka at K-1 World GP 2021: Yokohamatsuri on September 20, 2021.[81] Ishii won the fight by unanimous decision, after an extra round was fought.[82]
Ishii was scheduled to make his second professional kickboxing appearance against RUI at K-1 World GP 2021 in Osaka on December 4, 2021.[83] Ishii won the fight by unanimous decision.[84]
Ishii took part in the 2022 K-1 openweight tournament, held at K-1: K'Festa 5 on April 3, 2022. He faced BigBang heavyweight champion Kosuke Jitsukata in the tournament quarterfinals.[85] He won the fight by a second-round knockout.[86] Ishii withdrew from the tournament after this bout, due to a rib injury.[87]
Ishi made his professional boxing debut against Shuho Takayama (1–0) on August 14, 2022, as part of the "3150 Fight Vol 3" event.[90] He won the fight by majority decision.[91]
Ishii faced Chang Soo Han on January 6, 2023, as part of the "3150 Fight Vol 6" event. The fight was ruled a majority decision draw.[92] Ishii announced his retirement from the sport of boxing during the post-fight press conference.[93]
Submission grappling career
Ishii challenged Mason Fowler for the Submission Underground absolute championship at Submission Underground 19 on December 20, 2020.[94] He lost the match by submission in EBI overtime.[95]
Ishii returned at Submission Underground 20 on December 30, 2020, to face Craig Jones in the co-main event.[96] He was submitted with a rear-naked choke at 2:08 of regulation time.[97]
Ishii then competed against Andy Varela at Submission Underground 21 on March 28, 2021.[98] He lost the match in EBI overtime due to having the least ride-time.[99]
Personal life
Ishii was married for 9 months to Mika, a university student, divorcing in January 2011.[100] In 2013, he married singer Asuka Hayashi.[101] They divorced in 2016. They have one son.[102]