2005: AL wild card champions
After winning the 2004 World Series, the Red Sox were defending the title for the first time since 1919, and they made a strong push at the end of the year to get in as more than just a wild card. Heading into the final series of the year, a three-game set with the Yankees, the Red Sox were one game behind New York, needing a sweep because the Yankees held the tiebreaker for the division.
The Sox took two out of three, and, although they finished with the same record as New York, Boston had to settle for the wild card. Facing the Chicago White Sox in the ALDS, the Red Sox could not muster the same results to repeat as champions, and fell to the eventual world champion White Sox in three straight games to end their title defense.
The 2005 offseason would see many members of the 2004 World Series team leave Boston, including Johnny Damon, Kevin Millar, Bill Mueller, and Bronson Arroyo.