The A's started out as a favorite to win the AL West again, and played up to that, having the best record in baseball at the All-Star break. To bolster their starting rotation, they acquired pitchers Jeff Samardzija and Jason Hammel from the Chicago Cubs for several top prospects on July 4, and later acquired Jon Lester from the Boston Red Sox at the July 31 non-waiver trade deadline for Yoenis Céspedes. However, without the big bat of Cespedes, poor production from All-Stars Josh Donaldson and Brandon Moss, and an injury to closer Sean Doolittle, they struggled in August and the Los Angeles Angels of Anaheim caught up, sweeping them in a key 4-game series between the two teams. At the August 31 waiver trade deadline, the A's acquired first baseman Adam Dunn from the Chicago White Sox and cash considerations for a minor league player. Despite their struggles which continued into September, they made the playoffs on the last day of the season, and faced the Kansas City Royals in the Wild Card Game. While they carried a 7–3 lead going into the bottom of the 8th inning, they managed to relinquish it due to the Royals' baserunning skills coupled with ineffective pitching, allowing them to tie the game. They did regain the lead in the top of the 12th, but the Royals responded with 2 runs in the bottom of the inning, winning on a walk-off single by Salvador Pérez.