On November 25, 2013, the Nationals traded Abad to the Oakland Athletics for minor league outfielder John Wooten.

In his first season in Oakland, Abad pitched a career high 69 games with a career low 1.57 ERA in 57.1 innings.
Abad regressed the following season, allowing 11 home runs in under 60 innings.
The Athletics designated Abad for assignment after the 2015 season, and he later elected free agency.
On November 25, 2013, the Nationals traded Abad to the Oakland Athletics for minor league outfielder John Wooten.
In his first season in Oakland, Abad pitched a career high 69 games with a career low 1.57 ERA in 57.1 innings. Abad regressed the following season, allowing 11 home runs in under 60 innings. The Athletics designated Abad for assignment after the 2015 season, and he later elected free agency.
Fernando Abad