Honbasho

A honbasho (本場所^?) is an official professional sumo tournament. There are six held each year, a system established in 1958. Only honbasho results matter in determining promotion and relegation for rikishi (sumo wrestlers). Tournaments in general may be called basho.

A literal translation of honbasho is "main (or real) tournament". This term is used to distinguish these tournaments from display basho which are held as part of sumo tours, between the six major tournaments. Such display tournaments may have prize money attached but a wrestler's performance has no effect on his ranking. This type of sumo is often called hana-sumo (lit. flower-sumo) as it is not taken as seriously by the wrestlers.

Honbasho last for 15 days. Sumo wrestlers ranked in the top two divisions (makuuchi and jūryō) wrestle once each day, while those of the lower divisions wrestle seven times, approximately once every alternate day.

The first aim for most wrestlers is to achieve kachi-koshi, or a majority of wins, and thus ensure a promotion for the next tournament. In addition for each division there is a championship prize (yūshō) for the wrestler with the most wins at the end. A playoff on the final day is used to decide the winner in case of a tie.

Unless a playoff is required, two wrestlers will fight each other no more than once in a whole tournament. The bout schedule is set by a committee of sumo elders a day or two in advance of a tournament day, and may be announced from the sumo wrestling ring the day prior by a senior sumo referee. Although there is no fixed method, for the first half of a tournament the top division of sumo wrestlers will generally pair the best-ranking wrestlers (san'yaku) against the lowest-ranking wrestlers (maegashira) in the tournament, with the rest of maegashira fighting among ranks closer in strength. The schedule for the second half of the tournament will have mainly san'yaku fighting each other, with the remainder of the ranks determined by their win-loss records up to that point. One consideration is to minimize the necessity for a tiebreaker bout, particularly if a contender for the yūshō is lower-ranked and has thus far faced only other lower-ranked wrestlers.

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