The A's are two games off the pace for the American League's best record as they begin a three-game set against the host Seattle Mariners today.
The A's lost consecutive games to the Los Angeles Angels and will likely enter the postseason with the AL's second-best record behind the Boston Red Sox.
Mariners ace Felix Hernandez and veteran Oakland pitcher Bartolo Colon square off — the latter is tied for the AL lead in ERA while the former is making just his second start in 3½ weeks after an oblique injury.
Colon has won three consecutive starts as he finishes off his best season since going 21-8 for the Angels in 2005.
The 40-year-old issued just four walks over his last six starts and only 28 overall this season. Colon is 18-12 with a 3.90 ERA in 35 career starts against Seattle, including wins in both 2013 outings.