Question: Hiroaki Sato fought which Japanese mixed martial artist born on July 21, 1981?

full_context: Document 1: Minoru Suzuki: Minoru Suzuki (鈴木 実 , Suzuki Minoru , ring name: 鈴木 みのる) (born June 17, 1968) is a Japanese professional wrestler and mixed martial artist who is currently working for New Japan Pro Wrestling (NJPW) as a freelancer. He is the current NEVER Openweight Champion in his first reign.
Document 2: B.J. Penn: Jay Dee "B.J." Penn (born December 13, 1978) is an American professional mixed martial artist and Brazilian Jiu-Jitsu practitioner. Penn debuted and competed in the Ultimate Fighting Championship (UFC), and later in K-1. Prior to fighting for the UFC, he became the first American Gold medalist of the World Jiu-Jitsu Championship. In mixed martial arts, Penn has competed in the Featherweight, Lightweight, Welterweight, and Middleweight divisions. As a former UFC Lightweight Champion and UFC Welterweight Champion, he is one of only three fighters in UFC history to win titles in multiple weight classes. Penn was also a Co-champion in the UFC 41 Lightweight Tournament, due to an eventual draw opposite Caol Uno in the tournament finale. Through his tenures as champion, Penn unofficially unified the UFC Lightweight Championship (against Sean Sherk) and broke the all-time lightweight title defense record. Penn was inducted into the UFC Hall of Fame, as the inaugural inductee in the Modern-Era Wing by career-long rival Matt Hughes, during "International Fight Week" in July 2015.
Document 3: Fabiano Aoki: Fabiano "Cyclone" Goncalves Aoki (Japanese: ファビアーノ 青木 ; born in November 21, 1978) is a Brazilian light heavyweight kickboxer, fighting out of TARGET team in Japan. He was J-Network tournament champion, R.I.S.E., WPMF, HEAT and WBC Muaythai champion, competed in the K-1 and is currently signed to GLORY.
Document 4: Hiroaki Matsutani: Hiroaki Matsutani is a Japanese mixed martial artist. He competed in the Lightweight division.
Document 5: Sean Sherk: Sean Keith Sherk (born August 5, 1973) is a retired American mixed martial artist and former UFC Lightweight Champion. Sherk competed in the Ultimate Fighting Championship and was one of the first combatants to have been a championship competitor in multiple weight divisions (having also competed for the UFC Welterweight Championship). He was the second UFC Lightweight Champion in the organization's history after Jens Pulver vacated his title 5 years earlier. Sherk also spent time competing in the Japan-based organizations, PRIDE Fighting Championships and Pancrase; going undefeated in both promotions. He holds one of the longest undefeated streaks in mixed martial arts history, with only four career losses, all to fellow-UFC Champions. Sherk announced his official retirement from mixed martial arts competition in September 2013 having last fought three years prior.
Document 6: Kazushi Sakuraba: Kazushi Sakuraba (桜庭 和志 , Sakuraba Kazushi , born July 14, 1969) is a Japanese mixed martial artist and professional wrestler, currently signed to Rizin Fighting Federation. He has competed in traditional puroresu for New Japan Pro Wrestling and shoot-style competition for UWFi and Kingdom Pro Wrestling. He has fought in MMA competition in the Ultimate Fighting Championship, Pride Fighting Championships, Hero's and Dream. He is known as the "Gracie Hunter" or the "Gracie Killer" due to his wins over four members of the famed Gracie family: Royler Gracie, Renzo Gracie, Ryan Gracie, and Royce Gracie. In particular, Sakuraba is famous for his initial fight with Royce, which lasted ninety minutes.
Document 7: Yushin Okami: Yushin Okami (岡見 勇信 , Okami Yūshin , born July 21, 1981) is a Japanese mixed martial artist currently competing in the Light Heavyweight division of the UFC. A professional competitor since 2002, Okami has also formerly competed for PRIDE, Pancrase, M-1 Global, World Series of Fighting, and Professional Fighters League. He holds notable wins over Mark Munoz, Hector Lombard, Alan Belcher (twice),Anderson Silva (Via DQ), Nate Marquardt, former MMA fighter Evan Tanner and Mike Swick.
Document 8: Akihiro Gono: Akihiro Gono (郷野聡寛 , Gōno Akihiro ) (born October 7, 1974) is a Japanese mixed martial artist. He is best known for his clever and deceptive fighting style, and for his flashy ring entrances. His fighting style is characterized by skillfully avoiding strikes, using fast counter punches and generally getting the opponent to fight his way. He is one of only four men to beat Bellator Middleweight Champion Hector Lombard, and one of six to beat the DREAM Light Heavyweight Champion and former Strikeforce Light Heavyweight Champion Gegard Mousasi.
Document 9: Satoru Kitaoka: Satoru Kitaoka (北岡悟 , Kitaoka Satoru , born 4 February 1980) , is a Japanese shoot wrestler and mixed martial artist who most recently competed in the Lightweight division of RIZIN. A professional competitor since 2000, he has also competed for DREAM, Pancrase, DEEP, and World Victory Road. Kitaoka is renowned for his Catch wrestling abilities which he learned studying under two of Japan's most respected shoot wrestlers Masakatsu Funaki and Minoru Suzuki. In addition to mixed martial arts success, Kitaoka has also won several submission grappling tournaments, including being the reigning Brazilian jiu-jitsu and No-Gi Open Champion in both the 79.7 kg and Absolute divisions. In August 2008, he entered and won the 2008 Sengoku Lightweight Grand Prix. He is currently the DEEP Lightweight Champion.
Document 10: Satoshi Kojima: Satoshi Kojima (小島 聡 , Kojima Satoshi ) is a Japanese professional wrestler, currently signed to New Japan Pro Wrestling. As a singles wrestler, he was the first wrestler to hold NJPW's IWGP Heavyweight Championship and All Japan Pro Wrestling's Triple Crown Championship simultaneously, and one of three wrestlers to hold the IWGP Heavyweight Championship, Triple Crown Championship and NWA World Heavyweight Championship (the other two being Keiji Mutoh and Shinya Hashimoto). As a team, he and Hiroyoshi Tenzan are six-time IWGP Tag Team Champions and became the first team to win G1 Tag League and World's Strongest Tag Determination League on the same year. He and Tenzan are also former National Wrestling Alliance (NWA) World Tag Team Champions. Between the NWA, AJPW, and NJPW, Kojima has held 19 total championships.
Document 11: Cage Force: Cage Force(former name Demolition Octagon Gear (D.O.G.)) is a defunct Japanese Mixed Martial Arts (MMA) organization operated by Greatest Common Multiple (GCM) Communication. It was the first Japanese MMA organization to feature an octagon cage instead of a ring. Yushin Okami, Eiji Mitsuoka, Kuniyoshi Hironaka and Keita Nakamura experienced a cage match in D.O.G before contract with UFC. It enforced the Unified Rules of Mixed Martial Arts when the changed name to "Cage Force" from "D.O.G.", to prepare Japanese MMA fighters for the UFC. Cage Force tournament winner was entitled to a contract with UFC. Yoshiyuki Yoshida and Takeya Mizugaki have been contracted to the UFC and WEC by winning the tournament.
Document 12: Yasuhito Namekawa: Yasuhito Namekawa (滑川康仁 , Namekawa Yasuhito ) (born October 27, 1974) is a Japanese mixed martial artist who competes in the light heavyweight division. Namekawa made his Mixed martial arts debut for Fighting Network Rings in 1998. He fought in mainly Shoot fighting bouts until 1999 when Rings introduced the "King of King Rules". Throughout his career, Namekawa has fought for organisations such as Rings, Deep and Pride FC. His last fight to date was in 2008, with a professional Mixed martial arts career spanning ten years.
Document 13: Tetsuya Naito: Tetsuya Naito (内藤 哲也 , Naitō Tetsuya , born June 22, 1982) is a Japanese professional wrestler trained by and currently wrestling for New Japan Pro-Wrestling (NJPW). Within NJPW, Naito is a former IWGP Heavyweight, IWGP Intercontinental and NEVER Openweight Champion, the only wrestler who has held those three titles. He also held the IWGP Tag Team and IWGP Junior Heavyweight Tag Team Champion with former partner Yujiro Takahashi, with whom he teamed as No Limit. In addition to those, Naito is also a two-time winner of NJPW's premier singles tournament, the G1 Climax, having won it in 2013 and 2017, and the New Japan Cup, winning it in 2016. In 2016, "Tokyo Sports" named Naito the wrestler of the year.
Document 14: Hikaru Sato: Hiroaki Sato (佐藤 弘明 , Satō Hiroaki , born July 8, 1980) is a Japanese professional wrestler and mixed martial artist, better known by the ring name Hikaru Sato (佐藤 光留 , Satō Hikaru ) . Sato started his MMA career in February 2000, fighting for Pancrase Hybrid Wrestling. During the next eight years, Sato fought, on average, five times a year, compiling a record of 18 wins, 19 losses and four draws, which included fights against the likes of Keiichiro Yamamiya, Nathan Marquardt, Ryo Chonan and Yushin Okami. In May 2008, Sato transitioned into the world of professional wrestling, when he was signed by the Dramatic Dream Team (DDT) promotion. He has since had ten MMA fights. In November 2010, Sato first became a triple crown trios champion with Michael Nakazawa and Tomomitsu Matsunaga and then also won DDT's top singles title, the KO-D Openweight Championship. Sato remained affiliated with DDT until January 2014. He is currently working for the All Japan Pro Wrestling promotion, where he is a former two-time World Junior Heavyweight Champion and three-time All Asia Tag Team Champion, while also being a three-time winner of the Jr. Tag Battle of Glory tournament.
Document 15: Shinya Aoki: Shinya Aoki (青木 真也 , Aoki Shin'ya , born May 9, 1983) is a Japanese mixed martial artist and grappler currently competing in ONE Championship's and Rizin Fighting Federation's Lightweight division. A professional competitor since 2003, he is noted for being the DREAM Lightweight Champion, ONE Lightweight Champion, former WAMMA Lightweight Champion and former Shooto Welterweight Champion. Aoki is an A-class Shoot wrestler and BJJ black belt, both under his long-term mentor Yuki Nakai, as well as a black belt judoka. As of 2008, Aoki, along with DEEP champion Masakazu Imanari, and Sengoku champion Satoru Kitaoka have founded the "Nippon Top Team" as a group of elite Japanese grapplers competing in MMA. As well as his MMA credentials, Aoki has garnered several submission grappling accolades including two All Japan Jiu-Jitsu Championships, a Japan Open Jiu-Jitsu Championship, a Budo Open Championship, and an ADCC Japan Championship.
ground_truth: Yushin Okami