Gentry, 30, is hitting .264/.326/.299 (79 OPS+) in 80 games this year, including .273/.327/.333 (87 OPS+) against lefties. He is a standout defensive player, so he's worth having in the lineup despite the lack of offense. Gentry missed the start of the season with a lower back strain.
The A's called up speedster Billy Burns to replace Gentry on the roster. The 24-year-old is hitting .250/.333/.330 with 51 stolen bases in 91 Double-A games this year. Oakland acquired him from the Nationals in the Jerry Blevins trade over the winter.