As we entered the 21st Century, the MLB Playoffs extended into the end of October and into November for the first time. It made for the first ever World Series Games being played on Halloween. There have been 5 games played on Halloween. It began in 2001 when the Yankees beat the Diamondbacks in Game 4 with a walk off HR by Derek Jeter. The game went past midnight and Jeter was given the title Mr. November.
4 other World Series games have been played on Oct. 31.
Game 3, 2009 Yankees vs Phillies
Game 4, 2010 Giants vs Rangers
Game 4, 2015 Royals vs Mets
Game 6, 2017 Astros vs Dodgers
In 2018 MLB decided that baseball should not run into November and started the season earlier ensuring that there would not be a Halloween match up this year.