"I'm just trying to maintain the same approach every day," Smolinski said.
Smolinski went 1-for-4, and is now hitting .328, in Friday's 7-3 loss to the Pirates.
A's manager Bob Melvin said Smolinski's Triple-A defensive metrics even graded out as a "slight plus" over more than 20 games.
"It's always a little bit different in the big leagues, but he's played enough to where we feel comfortable about running him out there and we feel comfortable with him playing the position," Melvin said.
Smolinski's hitting .429 in 28 at-bats against lefties this year, including his pinch-hit three-run home run off Giants reliever Javier Lopez to give Oakland a 9-8 lead Monday. He posted a .400/.442/.700 slash line over 40 at-bats in June, establishing himself as a viable platoon option in the outfield.
"The way he's swinging the bat, especially against left-handed pitching, we had to find a way to get him in there," Melvin said.
Melvin also had an additional bench player at his disposal Friday, as Oakland recalled Tyler Ladendorf from Triple-A and optioned lefty Dillon Overton, who started Thursday against the Giants. Melvin expects to give Ladendorf a start Sunday.
It's the infielder's third stint with the A's this year. His most recent spanned from May 10 to June 17, when he went .087 (2-for-23) at the plate while appearing mainly as a utility infielder. He hit .344 in nine games with Triple-A Nashville since being sent down.
Melvin noted Ladendorf was "as comfortable as we've seen" prior to being optioned last month.
"Certainly when you get a guy back from Triple-A who is playing most every day, they're comfortable at the plate, so we'll need to get him in the game as soon as possible and that will probably be the day game Sunday," he said.
Mark Chiarelli is a reporter for MLB.com based in Oakland. This story was not subject to the approval of Major League Baseball or its clubs.