The MLB wild card first appeared in the postseason in 1995. It was created as part of the league’s 1994 realignment, which expanded MLB from two divisions in each league to three.
The new format gave a postseason berth to the best team in each league that did not win its division. In 1995, the first wild-card clubs were the New York Yankees in the American League and the Colorado Rockies in the National League. Both reached the Division Series, but neither won the pennant.
The timing can cause confusion because the wild card was officially introduced for the 1994 season. That postseason was canceled after the players’ strike, so no wild-card games were actually played that year. The first completed postseason featuring wild-card teams was therefore 1995.
MLB later expanded the format several times. A second wild card was added in 2012, followed by a third in each league in 2022, creating the six-team postseason field used under the current structure.