Yokozuna Hakuho, winner of a record 45 grand sumo tournament titles, informed the Japan Sumo Association on Monday of his decision to retire.

JSA President Hakkaku said during a meeting that the grand champion has conveyed his decision to call it a career, according to Hironori Yano, the head of the JSA's Yokozuna Deliberation Council.

The 36-year-old Mongolian-born great had been considering retirement after struggling to recover from a right knee injury that has kept him out of a number of tournaments in recent years, according to a source familiar with the matter.

Grand champion Hakuho shouts after defeating ozeki Terunofuji on the final day of the Nagoya Grand Sumo Tournament at Dolphins Arena in Nagoya, central Japan, on July 18, 2021, claiming his record 45th Emperor's Cup. (Kyodo) ==Kyodo

A source at his Miyagino stable said Hakuho has already told his stablemates of his decision to retire, adding that the grand champion was struggling badly during training.

His career appeared back on track when he returned to the ring to win the Nagoya Grand Sumo Tournament in July with a perfect 15-0 record, after missing all or part of the previous six tournaments due to injuries and a COVID-19 infection.

But he and 17 other wrestlers of the Miyagino stable were forced to skip the just-ended fall tournament due to multiple COVID-19 cases in the stable.

After acquiring Japanese citizenship in September 2019, Hakuho became eligible to run his own stable of wrestlers in the future.

He plans to instruct younger wrestlers as an elder attached to the Miyagino stable.

With 1,187 career wins and 1,093 makuuchi division victories, Hakuho's career was filled with records and defining moments.

The 69th yokozuna in the ancient sport's history, Hakuho, whose birth name is Monkhbatyn Davaajargal, debuted in the spring of 2001 and won his first top-division title at the summer meet in May 2006, when he first fought at the second-highest rank of ozeki.

File photo taken in April 2004 shows sumo wrestler Hakuho (L) posing for a photo with his stablemaster Miyagino after joining the top makuuchi division. Hakuho decided in September 2021 to retire. (Kyodo) ==Kyodo

Born in Ulaanbaatar, he was immersed in the Mongolian wrestling tradition from childhood. His father Jigjidiin Monkhbat competed in freestyle wrestling for Mongolia and won a silver medal at the 1968 Mexico City Olympics.

Standing 1.92 meters tall and weighing 155 kilograms, Hakuho was known for his wide-ranging attacking style and reached the highest rank of yokozuna ahead of the Nagoya meet in July 2007 aged 22 years and two months.

File photo taken in May 2006 shows ozeki Hakuho (C in front row) celebrating after winning his first career top-division title at the Summer Grand Sumo Tournament at Ryogoku Kokugikan in Tokyo. Yokozuna Hakuho decided in September 2021 to retire. (Kyodo) ==Kyodo

His fierce rivalry with fellow Mongolian-born grand champion Asashoryu captivated sumo fans until the latter's retirement in February 2010 left Hakuho as the only active yokozuna and the dominant force in the sport.

He won 63 consecutive bouts through November 2010, tying for the second-most all time. In January 2011, he became only the third wrestler, after former yokozuna Taiho and Asashoryu, to win six consecutive grand tournaments.

He claimed the all-time championship record with his 33rd career Emperor's Cup in January 2015, breaking the previous mark set by Taiho.

File photo taken in May 2007 shows sumo wrestler Hakuho accepting his promotion to yokozuna during a ceremony at his Miyagino stable in Tokyo. Hakuho decided in September 2021 to retire. (Kyodo) ==Kyodo

Despite his outstanding contributions inside the dohyo, Hakuho at times earned the disapproval of sumo authorities for not adhering to the sport's strict protocols.

After winning the March 2019 tournament, the last during Japan's Heisei era, he led the audience in an impromptu "tejime" clapping ceremony to mark the end of the era.

With ceremonies to formally conclude the tournament not completed, it was seen as a serious breach of etiquette, prompting a rebuke from the JSA and subsequent apology from the wrestler and his stablemaster.

"He boasts an outstanding record when compared to previous yokozuna," the yokozuna council's Yano said. "(But) being a yokozuna comes with greater responsibility, including acting as a role model."

"I hope he has time to reflect on what sumo really is and will help nurture deserving wrestlers (if he becomes a sumo elder)."

During the final years of his career, his time in the ring was interrupted by injury and the coronavirus pandemic.

He was reprimanded over his repeated absences by the JSA in November 2020 and was still subject to a warning when he returned to the ring in July following surgery to his troublesome right knee.

File photo shows Hakuho during practice in Tokyo in August 2021. (Kyodo)

His retirement leaves recently promoted Mongolian-born yokozuna Terunofuji, winner of the just-concluded Autumn Grand Sumo Tournament, as the only competing grand champion.

News of his retirement was met with shock and surprise in Mongolia, where Hakuho's success has contributed to the popularity of sumo broadcasts on TV.

His mother told Kyodo News she had not previously known of Hakuho's plans to retire, while stunned fans took to social media with tributes to "the pride of Mongolia."

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