Japan Diamond Softball League
Women's Softball League in Japan
The Japan Diamond Softball League (JD.League) is a Japanese women's softball league that consists of 16 teams (8 in the East Division and 8 in the West Division). The league is the premier women's softball league in the country. The league was formed in 2022 and is headquartered in Shinjuku, Tokyo.
The JD.League is a member of the Japan Top League Alliance, which comprises the top-tier sports leagues in Japan. Nitori entered into the title partnership with the JD.League, and thus the league is officially called Nitori JD.League.
History
The first national women's softball league was founded in 1968, as the Japan Softball League. In 1994, the league's First Division expanded from 8 to 12 teams and adopted a postseason with the page playoff system. Since then, this season's format was lasted until 2021, although there were minor changes.
In 2021, the league announced a new top-tier women's softball league is planned for 2022, the Japan Diamond Softball League (JD.League). All 12 teams from the First Division and four teams from the Second Division, i.e., 16 teams in total joined in the new league.
Begin with the source’s own compact description: “Japan Diamond Softball League” is women's Softball League in Japan. The dossier treats that line as a proposition to test through Japan, Diamond and Softball, not as a finished interpretation.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Jun 19, 2026. The linked authority identifier is Q111700934. None of the 2 selected statements returned an explicit reference. The first chronological checks are 2022, 1968, 1994 and 2021.
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This entry incorporates text from “Japan Diamond Softball League” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.