NBC Sports California has learned that the A's will activate catcher Chris Herrmann from the 60-day injured list and option Beau Taylor to Triple-A Las Vegas.
The A's will also have to make a corresponding move to make room for Herrmann on the 40-man roster. Oakland will likely transfer either Marco Estrada or Nick Hundley to the 60-day IL.
Herrmann has missed the first 85 games of the season after undergoing arthroscopic surgery on his right knee in March. The 31-year-old signed a one-year, $1 million contract with the A's this offseason after spending parts of seven seasons with the Twins, Diamondbacks, and Mariners.
Herrmann performed well on his rehab assignment with Triple-A Las Vegas, slashing .333/.397/.667 with four home runs and 13 RBI in 13 games. The switch-hitter figures to split time with Josh Phegley, who is having a breakout season with a .263/.304/.470 slash line and a career-high nine homers and 42 RBI.
Taylor, 29, went 4-for-19 with two home runs and four walks in eight games with the A's this season. He made his major league debut last year at the age of 28 after spending eight years in the minors.
The A's open a three-game homestand against the first-place Minnesota Twins on Tuesday night.