Opening Day
The day on which professional sports leagues begin their regular season
Opening Day is the day on which professional baseball leagues begin their regular season. For Major League Baseball (MLB) and most of the American minor leagues, this day typically falls during the first week of April, although in recent years it has occasionally fallen in the last week of March. Since 2023, Opening Day falls on the last Thursday of March. In Nippon Professional Baseball (NPB), this day typically falls during the last week of March.
For baseball fans, Opening Day serves as a symbol of rebirth; writer Thomas Boswell once penned a book titled Why Time Begins on Opening Day. Pre-season exhibition games are usually played in the month before Opening Day, during spring training. A home opener is a team's first game of the season on their home field.
Equivalents to Opening Day occur throughout the sport, including minor leagues, college baseball, high school, and youth leagues. Because MLB generally begins its season earlier than the other professional baseball leagues, its Opening Day is the one most commonly recognized by the general public. Most minor leagues start a few days later, but within the same week; the short season Class A and Rookie leagues are exceptions, as they begin in June.
This brief starts where responsible research should: with the source description of “Opening Day” as the day on which professional sports leagues begin their regular season. Everything that follows is an evidence route, not borrowed authority.
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The subject matters to the general reference register because the source frames it as the day on which professional sports leagues begin their regular season. Its deeper value depends on whether names, dates, institutions and citations support that framing.
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 Mar 27, 2026. The linked authority identifier is Q903416. None of the 0 selected statements returned an explicit reference. The first chronological checks are 2023.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The source lead contains qualifying language; that uncertainty should survive quotation, summary and reuse. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
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This entry incorporates text from “Opening Day” 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.