Harumafuji admitted to assaulting fellow Mongolian wrestler Takanoiwa during a regional sumo tour in late October 2017.

[8] In September 2007, under the komusubi rank, Ama defeated new yokozuna Hakuhō on the opening day and also beat two ōzeki.

He also memorably defeated newcomer Gōeidō with a spectacular technique known as okuritsuriotoshi or "rear lifting body slam.

On the 8th day of the May 2008 tournament, he amazed audiences by defeating Wakanohō with a perfectly executed utchari or spin throw on the bales.

[12] On the 10th day, Ama also threw yokozuna Hakuhō into the seats with an overarm throw, ending his winning streak.

On November 26, 2008, Ama was promoted to ōzeki by the Sumo Association, and on the occasion had his fighting surname changed to Harumafuji.

On the fifth day he returned to the ring in his customary black mawashi, rallied, and by the end of the tournament secured an 8–7 majority of wins.

He bounced back in July as he won his third championship without losing a bout, beating Hakuhō on the last day for his first zenshō-yūshō (winning every match in the tournament).

He attended a ceremony bestowing him the title, and said "With the awareness of what it means to be a yokozuna, I will devote my body and soul to the way of sumo.

"[6] He performed his first yokozuna dohyō-iri (ring-entering ceremony) on September 28, 2012, in front of 3,000 people at the Meiji Shrine in Tokyo, with Aminishiki as the sword carrier and Takarafuji as the dew sweeper.

[29][30][31] Harumafuji's first tournament as a yokozuna in November 2012 was a disappointing one, as he gave up a kinboshi to Okinoumi on just the second day, and from 9–1 up finished with a 9–6 record.

Despite being criticized heavily for his lackluster debut at the rank of yokozuna, Harumafuji bounced back with a tremendous showing in the following tournament winning all 15 matches, for his third zenshō-yūshō.

[35] This means his title drought had extended to two years by the time he made his comeback at the November 2015 tournament in Kyushu.

[37] In January 2016 Harumafuji defeated Hakuhō on the final day to end with a 12–3 record which placed him in a tie for second behind the upset winner Kotoshōgiku.

In March he posted a moderate 9–6 in a tournament which saw him struggling with a knee injury in addition to his chronic ankle problems.

He defeated his main challenger, Kisenosato, on day 13 and avoided a play-off by beating Hakuhō by yorikiri in the last match of the tournament.

[43] He was defeated by maegashira Kotoshōgiku on Day 3 after he apparently stopped fighting after the initial charge, expecting the bout to be called as matta.

[48] Takanoiwa's head injury, which included a skull fracture, forced him to miss the entire November 2017 tournament,[4][49] which subsequently resulted in his demotion from maegashira #8 to jūryō #3.

[52] Mongolian yokozuna Hakuhō, who was present at the incident, told the press before Day 5 of the tournament that he owed a "deep apology to the sumo world and the public.

"[53] Contrary to media reports, Hakuhō insisted Harumafuji was holding a beer bottle, but it slipped out of his hands.

[53] Conflicting reports over subsequent days suggested an ice pick, ashtray, microphone or karaoke remote control may have been used instead, while Harumafuji himself said he used only his bare hands.

[54] The day after the November 2017 Tournament ended, the Yokozuna Deliberation Council (YDC) convened at the Ryōgoku Kokugikan in Tokyo and agreed that an "extremely harsh punishment" be administered to Harumafuji.

He did not go into details about the incident but added, "I had heard that he was lacking in manners and civility and thought it was my duty as a senior wrestler to correct and teach him.

[60] On December 20, 2017, the YDC said that they would have recommended Harumafuji's resignation had he not already retired, and that there needed to be a clear standard set for future cases.

The chairman of the YDC said "Harumafuji, a yokozuna who should be a role model to all wrestlers, showed abusive behavior that led to injury.

[63] On October 4, 2018 Takanoiwa filed a lawsuit in Tokyo District Court seeking 24 million yen in damages from Harumafuji, after negotiations over an informal settlement broke down.

Hakuhō was criticized by the Yokozuna Deliberation Council for expressing his hope that Harumafuji would return to sumo after his November 2017 tournament victory, and leading the crowd in banzai cheers.

[74] In 2014 he attended classes at the graduate school of Hosei University, studying the Mongolian economy and education system.

Now teaching 1,800 students, Harumafuji also received compliments from the university's chancellor, who congratulated him on "his daily behavior and attitude in the ring.

"[77] Sanshō key: F=Fighting spirit; O=Outstanding performance; T=Technique     Also shown: ★=Kinboshi; P=Playoff(s) Divisions: Makuuchi — Jūryō — Makushita — Sandanme — Jonidan — Jonokuchi