**The 2026 MLB postseason's longest game reached 12 innings in World Series Game 4, a Rays 4-3 victory over the Brewers on October 27 that featured extended bullpen usage after regulation.** No other contest across the Wild Card, Division Series, League Championship Series, or remaining World Series games exceeded regulation or brief extras, keeping the maximum at 12. This outcome aligns with trader pricing showing elevated implied probability for an 11+ inning game but sharply lower odds for 13+ or beyond, reflecting the absence of marathon contests or weather delays that historically extend playoff affairs. The Brewers' series win in five games and the Rays' earlier ALCS path produced no additional late-inning drama or roster factors that could have prolonged another matchup.