Sumo Wrestling - who can beat the best?

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Sumo is the national sport of Japan. Wrestlers (Rikishi) are ranked in a ladder format. If you win more than you lose, you move up the ladder (Banzuke).

At the top of the ladder sits the Yokozuna. This is the highest level, with only 73 ever in the long history of Sumo.

For lower ranked wrestlers, beating a Yokozuna is a major accomplishment. This is even accompanied by a cash prize, 15,000 yen a month for the remainder of his career.

Intuitively you would think that those highest on the ladder should be the ones to defeat the Yokozuna most often. Is that true?

I looked at the match history from sumodb for the last 20 years, or 2582 Yokozuna matches. Here is what the win % looks like for the next 8 ranks below the top. Note that it is very rare for very low ranked wrestlers to face a Yokozuna, so I stopped when sample size became too low (below M5).

The closest ranking (Ozeki) does have the best win percentage, although it is only 27%. What is weird is the reverse trend between Komusubi (13%) and M1 (16%).

Now consider that not all Yokozuna are equal. Hakuho is widely considered the best of all time, and this supports that claim. Chances against him are significantly lower than other Yokozuna.

If sumo interests you at all, try out the youtube video that led me down the rabbit-hole here.

	Ozeki	Sekiwake	Komusubi	Maegashira 1	M2	M3	M4	M5
Win % Against Each Yokozuna
Asashoryu	28%	18%	11%	11%	8%	10%	7%	5%
Hakuho	20%	20%	9%	6%	5%	3%	3%	19%
Harumafuji	32%	27%	14%	33%	17%	15%	19%	27%
Kakuryu	44%	43%	20%	18%	16%	19%	10%	22%
Kisenosato	25%	50%	50%	50%	42%	22%	40%	100%
Musashimaru	50%	44%	20%	45%	8%	30%	0%	0%
Takanohana	0%	0%	0%	0%	0%	100%	50%
Terunofuji	0%	25%	0%	0%	0%	0%	33%	0%
Match Count Against Each Yokozuna
Asashoryu	119	74	73	72	72	63	41	19
Hakuho	213	133	141	144	134	116	61	21
Harumafuji	68	48	49	45	46	39	37	15
Kakuryu	59	42	54	60	51	43	21	9
Kisenosato	4	6	10	16	12	9	5	1
Musashimaru	10	9	10	11	12	10	7	5
Takanohana	4	2	2	4	3	3	2	0
Terunofuji	3	4	4	4	4	4	3	2