The Athletics entered the season hoping to win a third consecutive American League West championship; to that end, the team made a number of key signings and trades during the 2013–14 MLB offseason.

Unexpectedly strong performances by starting pitchers Scott Kazmir, Jesse Chavez, and Drew Pomeranz enabled much of this surge; the Athletics' red-hot hitters (particularly sluggers Josh Donaldson, Yoenis Céspedes, and Brandon Moss) also played a major role.

In part because of this, the Athletics traded noted prospects Addison Russell and Billy McKinney, along with starting pitcher Dan Straily, to the Chicago Cubs for two starters (ace Jeff Samardzija and veteran Jason Hammel) on July 4.

On July 31, with a scant 2.5 game lead over Los Angeles, the Athletics stunned the league by trading Yoenis Céspedes for all-star starter Jon Lester and outfielder Jonny Gomes.

In the 12th inning, the Athletics' took an 8-7 lead on an Alberto Callaspo line drive; the Royals, however, would again rally for a 9-8 walk-off victory (their first playoff win in 29 years).

By mid-August, however, the Athletics had quickly begun losing ground in the AL race with a record of 11–25 through a 36-game span from August 10, to September 19, and were in the midst of what some called an historic collapse.

This deal sent All Star left fielder Yoenis Céspedes to the Boston Red Sox in return for starting pitcher Jon Lester and veteran outfielder Jonny Gomes.

Kansas City responded in the bottom half of the inning, and trimmed Oakland's Lead to 1 after a Billy Butler single, scoring Nori Aoki.

Both teams remained scoreless until the top of the 12th, where Alberto Callaspo scored Josh Reddick on a single to left field, which put the Athletics up 8-7.