Valdez was optioned to Triple-A Nashville on Friday.
This move suggests that Kendall Graveman's bullpen session Friday went well and that Graveman will indeed return to rotation next week after missing one start due to a shoulder injury. Valdez wasn't great Thursday in a spot start -- his first major-league start since 2010 -- but he at least kept the A's in the game with four innings of three-run ball against Seattle.