User:Kashi/Jun'i-sen

Kashi/Jun'i-sen
Category	Qualifier for the Meijin-sen
Outline
Time held	June - March
First held	1947 (term 1)
Time control	6 hours per side
Organizer(s)	Mainichi Shimbun Asahi Shimbun Japan Shogi Association
Official site	https://www.shogi.or.jp/match/junni/index.html
Records
Notes	Longest stay in class A: Yasuharu Oyama (44 terms) Longest continuous stay in class A: Yasuharu Oyama (44 continuous terms)

The Jun'i-sen (順位戦 Jun'isen) or Ranking League is a tournament hosted by the newspapers Mainichi Shimbun and Asahi Shimbun in cooperation with the Japan Shogi Association, which acts as a qualifier for the Meijin-sen. The player with the best record in class A will challenge for the Meijin title.

Summary

The league consists of 5 classes A, B1, B2, C1, and C2. The top finisher of class A will become Meijin challenger. Even though the Meijin themselves do not participate in the league, their years as Meijin are counted as years in class A as well when calculating career records.

Each class normally conducts a round-robin tournament from June to March of the following year, from which the seeds of next year's league are decided. Most new professionals start their career in class C2, with some starting in Free Class instead (not participating in the league). Current rules do not allow skipping classes in promotion, which means that new players have to play for at least 5 years from their debut to challenge the Meijin.

Players can be promoted by moving up classes in the league, with their game fee earnings also increasing depending on their class. Other than revenue, players in higher classes also benefit by being exempt from certain preliminary rounds in other tournaments. However, a player can be forced to retire immediately or after a fixed time if they lose rights to participate in the league, a trait not seen in any other tournament.

Around the first third of March every year, all 5 games of class A's last round will be played on the same day, and most of the time the Meijin challenger and the 2 demotees will only be decided then. Due to the long duration of the games, this day is called "the shogi world's longest day", attracting attention outside of the shogi world as well. From 2014 onwards, with the exception of 2017, these games have all been played at the Fugetsuro restaurant in Aoi Ward, Shizuoka City, Shizuoka Prefecture. These games are analyzed live on giant boards at the JSA headquarters in Sendagaya, Tokyo, the Shogi Kaikan at Fukushima, Osaka, and the Osu Hall at Naka, Nagoya. They are also streamed live on TV and online.

From term 66, the Mainichi Shimbun and the Asahi Shimbun have cooperated to host the tournament. On even-numbered terms, Asahi will be listed as the first sponsor and on odd-numbered terms the Mainichi Shimbun will be listed first.

System

Classes and promotion/demotion

The system is comprised of the 5 classes A to C2, along with Free Class players who will not be playing. The player with the best result of class A gains the right to challenge the Meijin.

Each class's mechanics are described below. Classes that have empty slots (due to players retiring or passing away) will be adjusted on a case-by-case basis.

Current rules

Class	Capacity	Game count	Promotion	Demotion/demotion points
Meijin	1	Best-of-7 match with the challenger	Title is defended after winning 4 games against challenger	Return to class A after losing 4 games (as seed 1)
A	10	Round-robin + Playoff 9 games + BO7 match (challenger)	(for challenger) Title is acquired after winning 4 games against Meijin	2 players (to B1)
B1	13	12 round-robin games	2 players (to A)	3 players (to B2)
B2	no fixed capacity	10 games with other players in same class	3 players (up 1 class)	Players with 2 accumulated demotion points (down 1 class)
C1
C2				Players with 3 accumulated demotion points (to Free Class or retirement)
Free Class	Demotees from C2	no games (participation in other tournaments still possible)	Satisfy at least 1 promotion requirement (to C2)	Up until either one of the below, whichever is faster: Stayed in Free Class for 10 years End of season where player reaches 60 years of age If a promotion requirement is not satisfied during the period above then the player must retire after they have finished all games in official tournaments.
	Voluntary transfer		Can't return to league	After a certain number of years (1-8) have passed the player will retire after either of the below is satisfied, whichever is faster: End of season where player reaches 65 years of age Another 15 years have passed

Demotion points (for classes B2, C1, C2)

Requirement for accumulation

• Class B2: The formula for number of players receiving demotion point is (players in class / 4).
• Classes C1/C2: The formula for number of players receiving demotion point is (players in class / 4.5).

Requirement for removal

• For class C2, removal of demotion points is limited to players with 2 points only. The 1st demotion point will never be removed if the player doesn't promote/demote.
• A player can get a demotion point removed if they end the league with more wins than losses or finish 5-5 2 years in a row.
• If a player meets both the requirement for accumulation and removal of points in the same season, there is no change to said player's status.
• When a player promotes or demotes, their demotion points are reset to 0.

Headbumping

When multiple players share the same result, with the exception of a tie for Meijin challenger, no playoff will be held. Instead, players will be ranked based on their seed from the start of the season to determine those who promote and those staying behind. When such an event happens, for lower-seeded players failing to promote, it is called headbumping (頭ハネ atamahane). The contrary is also true: players can remain or suffer a demotion point based on seed alone, hence a single win in class C2 can later affect one's remaining or demoting from class A.

In class A of the 27th Ranking League held in 1972 contested by 11 players, Rensho Nada 8-dan, who was on break the term before, finished 9th overall. Normally, this meant that he was among the 3 players to be demoted, but Nada was not demoted due to his 5-5 result. Regarding this, on the 4 April 1973 issue of the Asahi Shimbun, Nada has said that it "would have been a big problem if 5-5 finishers were demoted". A description of this rule was also found in the August 1958 issue of the Kindai Shogi magazine, indicating that it had been known among players for a long time. However these rules did not exist on paper and the JSA did not have these rules either. As a result, in the 76th Ranking League, where class A was also contested by 11 players, the JSA, the Mainichi Shimbun, and the Asahi Shimbun agreed that if this were to occur again, the player would still be demoted as per usual. On the JSA's website, this was demonstrated with a hypothetical playoff of 7 players who finished 5-4. If a potential demotee failed to challenge the Meijin, they would still be demoted anyway.

Exceptions related to promotion

Generally, classes B2 to C2 will have 3 promotees each (from term 79). If the number of players finishing 10-0 exceeds the amount of slots, from term 77, it has been clarified that all 10-0 finishers will be promoted regardless of seed. Before this clarification, there has been no cases of this occuring. There will be no problem if this occurs in classes C2 or C1 as the classes above them both have no fixed player count. However, if this occurs in class B2, next term's class B1 will have an excess amount of players. For example, if 4 players in class B2 finished 10-0, class B1 will play with 14 players next term, and 4 players will be demoted next term. As for classes B1 and A, since these classes play round-robin, there will never arise more than one 10-0 finisher.

Adjustments related to over/undercapacity classes

Classes A and B1 have a fixed capacity, which means that problems can arise from one of the causes below.

• Overcapacity classes
  • Players returning from break.
  • (only for class B1) More than 3 10-0 finishers promoting from class B2. See Exceptions related to promotion.
• Undercapacity classes
  • Players retiring/passing away before the draw is conducted, leading to a deficit in their classes.
  • Players retiring/passing away in the midst of a league, leading to the rest of their games being treated as a no-show win for their opponents, and the class they promote/demote to or remain in will have a deficit.
  • (only for class B1) Deficit in demotees due to players on break in class A.
  • (only for class B1) Players voluntarily transferring to Free Class.

At the beginning of the season, if there is a player deficit/surplus, the number of demotees will be adjusted accordingly so as to return to the normal capacity. For example, if class A has 11 players, 3 players will be demoted, and if it has 9 players, 1 player will be demoted. Class B1 will also take into account the extra/missing demotees from class A if this occurs.

Players on break

If for unavoidable reasons such as illness, a player can submit a notice of absence in the 1-year period before the next league to be excluded from all tournaments in that season. If this happens, the player will not be demoted in their first season of absence and will be assigned the lowest seed in their class when they return. This is called "overhang" (張出, haridashi). If they return in class A, class B1 will play with a player deficit and class A with a surplus. However, if the player is absent for 2 years or more, they will start demoting if in class A or B1 and receiving demotion points if in class B2 and below. After they have been absent from class B2 for 3 years, they will directly demote regardless of demotion point count. However, if a player decides to go absent in the middle of a season, the rest of their games will be ruled as a default loss and they will be demoted/promoted as per usual.

If a player passes away in the middle of a season, the rest of their games will also be ruled default losses, with their opponent receiving a default win. However, the deceased player's losses will not count towards their career statistics. If a player is promoted by way of a default win against a deceased player, their date of promotion will be the scheduled game date.

Challenger-deciding playoff

If there are multiple players with equal results for the top spot in class A, a ladder-style playoff will be conducted, with the lowest ranked players at the bottom and the highest ranked player at the top.

There have been 21 playoffs held since the new system was established in term 5. Of these, 5 were held with 3 players and 4 with 4 players or more. The most players to have played in the playoff is 6 (in term 76).

3-man playoff (5 terms)

Terms 7, 12, 44, 45, and 61 (seasons 1953, 1958, 1986, 1987, and 2003 respectively).

4-man or more playoff (4 terms)

• Term 37 (1979 season) - 4-man (6-3 result)
  (from highest seed) Keiji Mori 8-dan, Kunio Yonenaga Kio, Yasuharu Oyama 15th Lifetime Meijin, Tatsuya Futakami 9-dan
  Challenger: Yonenaga (lost title match 2-4)
• Term 50 (1992 season) - 4-man (6-3 result)
  (from highest seed) Koji Tanigawa Ryuo, Yoshikazu Minami 9-dan, Michio Takahashi 9-dan, Yasuharu Oyama 15th Lifetime Meijin
  Challenger: Takahashi (lost title match 3-4)
• Term 73 (2015 season) - 4-man (6-3 result)
  (from highest seed) Hisashi Namekata 8-dan, Akira Watanabe 2-crown, Toshiaki Kubo 9-dan, Akihito Hirose 8-dan
  Challenger: Namekata (lost title match 1-4)
• Term 76 (2018 season) - 6-man (6-4 result)
  (from highest seed) Akira Inaba 8-dan, Yoshiharu Habu 3-crown, Akihito Hirose 8-dan, Yasumitsu Sato 9-dan, Toshiaki Kubo Osho, Masayuki Toyoshima 8-dan
  Challenger: Habu (lost title match 2-4)

With the exception of Yoshiharu Habu Ryuo in term 61, no challenger selected via 3-man or above playoff has defeated the reigning Meijin in the title match.

Assignment of seed

The seeds in each class are assigned in order listed in the table below from top down.

	Class C2	Class C1	Class B2	Class B1	Class A
1	Demotees from class above (excluding absentees, in order of result)				Loser of title match
2	Returning absentees relegated from class above				-
3	Players remaining in class (excluding those who accumulated demotion points, in order of result)			Players remaining in class (in order of result)
4	-	Promotees from class below (in order of result)
5	Players having accumulated demotion points (in order of result)			-	-
6	Incoming players from Free Class having achieved promotion from April 1 to September 30 (in order of promotion)	-	-	-	-
7	Winner and runner up of previous season's first 3-dan League	-	-	-	-
8	Incoming players from Free Class having achieved promotion from October 1 to March 31 (in order of promotion)	-	-	-	-
9	Winner and runner up of previous season's second 3-dan League	-	-	-	-
10	Returning absentees who were not demoted

• Results in the above table are sorted in descending order of victories and then in ascending order of seed for players who have the same number of victories.
• For items 6 and 8, players coming from Free Class are sorted by date of qualification for return. The earlier the date, the higher the player's seed.
• If a playoff occurs in class A, the final ranking is decided based on seed alone for players who fail to challenge the Meijin. The challenger will always become Meijin or get seed 1 next term.
• For players going absent for 2 consecutive years or more:
  • If in class A or B1, the player is immediately demoted.
  • If in class B2 and below, the player gets a demotion point after 2 years and is demoted after 3 years (they get a 2nd demotion point if in class C2).

Time control

• Class A: 6 hours a side (stopwatch method)
• Class B1 and below: 6 hours a side (chess clock method)

At 6 hours a side, the Ranking League has the longest time control of all qualifying and final rounds of title tournaments, even longer than all 1-day title matches. However, Ranking League games still start at 10am like other non-title match games, with a 40 minute break each for dinner and lunch. Consequently, most league games go on until late at night, and sometimes even to the day after.

From the 75th Ranking League (2016 season) onwards, games in class B2 and below were to be played with chess clock time control rather than the traditional stopwatch method. This is to accomodate for the fact that apprentice school members, who are responsible for record-keeping, sometimes have to take days off school for their job. About this change, Akira Watanabe has predicted that games "will end 1 hour earlier (on average)". The chess clock method has also been applied to class B1 since the 81st Ranking League.

Moreover, from June that year, the lunch and dinner breaks in games were also shortened from 50 to 40 minutes, with the same intention of shortening games.

If both players use their time well, they will enter byoyomi by about 11:20pm for class B1 and below and 0:30am for class A.

Pairings

All pairings for each class have been decided before the tournament, along with their turn orders, hence furigoma is not conducted before games.

Turn order in games follow the JSA's guidelines which have been published online.

• Turn order for players in each class should be balanced (meaning that players in class B2 and below will play 5 games each with Sente and Gote, players in class B1 will play 6 games with each color, and players in class A will play 4-5 games as Sente). Care should be taken to keep the turn orders balanced, and no player should play with the same color for 3 rounds in a row, neither should they play with the same color for their first or last 2 games (this requirement is not mentioned on the JSA site, but on Asahi Shimbun's). These equalizations are carried out on an annual basis however, so a player in class A who played 5 games with Sente in a season may still play 5 games with Sente the next.
  (However, turn order in class A playoffs are decided with furigoma.)
• For classes A and B1 (round-robin),
  • Players will not play their first or last game with their last opponent the season before. However, this does not have effect if the player has just demoted/promoted or they were given a bye on the last round of the previous season.
  • Players will not play their first game or last 3 games with their teacher, relatives, or students of the same teacher.
• For class B2 and below (no round-robin),
  • Players will not play their teacher or relatives.
  • Players will not play their first game or last 3 games with students of the same teacher.
• Otherwise for class B2 and below pairing priority is as follows.
  • Pairings which have not occurred for the past 3 seasons (required for classes B2 and C1)
  • Pairings which have not occurred for the past 2 seasons (as much as possible)
  • Pairings where a) neither player's class changed after the previous term, or b) pairings where one or both players have changed classes.
  • Pairings where a) neither player's class changed after the previous term AND they have played the previous term but NOT 2 terms ago, or b) pairings where one or both players have changed classes.
  • Players will not play against opponents they have met for the past 2 terms.

Computer and human pairing

All league pairings used to all be made manually, but computers have been employed for this since the late 1990s for class B1 and below.

Pairings in class A however have always been made manually with Western playing cards. Specifically, 10 cards Ace to 10 are flipped down representing 10 players in the class, and 2 cards each are picked at random to decide pairings. Turn order is also decided with playing cards, where a card is pulled at random from the deck and an experienced player marks a circle or cross depending on the card's color, making adjustments as necessary to follow the rules. At the very end another card is selected to decide if circles or crosses represent Sente.