The Oakland Athletics' 2008 season marked their 40th year in Oakland, California. It was also the 108th season in franchise history. The team finished third in the American League West with a record of 75-86.
The Athletics were not expected to contend for the American League West title in 2008. Despite this, the team remained near first place well into July. The Athletics fortunes peaked on July 11, when a 9-2 rout of the Angels allowed them to pull within four games of first place. The team then lost 44 of its 68 remaining games. The slide saw the Athletics finish 24.5 games behind the Angels, who clinched the division for a second consecutive year.
The Athletics struggled at the plate for most of the season. Particularly troubling was the team's lack of power hitting; apart from Jack Cust, who hit 33 home runs, no Athletic hit more than 13. Oakland ultimately finished 11th (out of 14 American League teams) in this category. All told, the Athletics scored fewer runs (646) than any other American League team in 2008.
Off-season
Potential free agents
Outfielder Jeff DaVanon, catcher Mike Piazza and outfielder Shannon Stewart all filed for free agency after the 2007 season. DaVanon was signed to a minor league contract by the Athletics on August 10, 2007, after being let go by the Arizona Diamondbacks less than a week later. His contract was purchased on August 17, following an injury to Mark Kotsay, who was plagued with injuries in 2007. He posted a .238 batting average and no home runs in 26 games for the Athletics. Piazza was signed in the previous offseason to a one-year contract which began Piazza's career as a designated hitter. In early May, Piazza was placed on the disabled list after suffering an injury while sliding into third base against the Boston Red Sox. Piazza was activated from the disabled list on July 20 but saw limited action after that as Jack Cust, who the Athletics brought in as a replacement, put on a big show once he joined the team. Piazza played in a total of 83 games in 2007 and batted .275 with 8 home runs. Stewart was also signed in the previous offseason to a one-year contract after missing most of the 2006 season. Stewart played in 146 games in 2007 and led the team in batting average (.290).
October
October 5: Outfielder Dee Brown, pitcher Ron Flores, infielder J. J. Furmaniak, pitcher Brad Halsey, pitcher Shane Komine, catcher Adam Melhuse and pitcher Jason Windsor were outrighted to the minor leagues. Brown, Flores, Furmaniak and Melhuse eventually declined their assignments and became free agents. October 6: The Athletics announced that they would not renew the contracts of bullpen coach Brad Fischer, third base coach Rene Lachemann, and bench coach Bob Schaefer for the 2008 season. October 11: Pitcher José García was claimed by the Athletics off waivers from the Florida Marlins. García had missed the entire 2007 season following Tommy John surgery. October 13: Pitcher Jay Marshall and outfielder Kevin Thompson were claimed off waivers by the Boston Red Sox and the Pittsburgh Pirates, respectively. A Rule 5 draft selection from the Chicago White Sox, Marshall saw action in 51 games in 2007, mainly as a left-handed specialist. He put up a 1–2 record and a 6.43 ERA. Claimed off waivers from the New York Yankees on September 7, 2007, Thompson played in 9 games for the Athletics in the final month of the season, batting .071 with no home runs.
October 16: Ron Romanick was added to the Athletics coaching staff and will serve as the bullpen coach for the 2008 season.
October 23: Don Wakamatsu was added to the Athletics coaching staff and will serve as the bench coach for the 2008 season.
October 25: Outfielder Chris Snelling was claimed off waivers by the Tampa Bay Devil Rays. Acquired on May 2, 2007, from the Washington Nationals for Ryan Langerhans, Snelling played in just 6 games before being placed on the disabled list on May 16 and never played in another game for the Athletics. That same day Connor Robertson was outrighted to the minor leagues. Robertson appeared in 3 games in 2007 and posted an 18.00 ERA. Tony DeFrancesco was also added to the Athletics coaching staff and will serve as the third base coach for 2008.
November
November 2: Pitcher Colby Lewis was claimed off waivers by the Kansas City Royals. Lewis mainly worked out of the bullpen for the Athletics in 2007, posting a 6.45 ERA and an 0–2 record in 26 games.
November 18: Infielder Marco Scutaro was traded to the Toronto Blue Jays for two minor league pitchers, Graham Godfrey and Kristian Bell. Scutaro, a valuable backup infielder, played in 104 games in 2007 for the Athletics, posting a .260 batting average and 7 home runs.