A's assistant general manager David Forst said Ramirez expects to return to the lineup Monday, the San Francisco Chronicle is reporting.
Ramirez is on a 10-game assignment with the River Cats. He is eligible to join the A's on May 30 after his 50-suspension for violating Major League Baseball's drug policy ends.
Ramirez went 0-for-4 with three strikeouts Saturday for Sacramento.
A's manager Bob Melvin said he hadn't received a detailed update on Ramirez's condition.
"We're' looking to see if the bat speed's still there and how he gets through these 10 days," Melvin said. "If there's a time frame where he's losing some time, we might back it up or whatever. We'll rely on the people that are watching him at this point. We have enough going on here to where my focus is more on what's going on here. We have some DL issues, guys coming back before he will be here. I'm a little more focused on that now, but I certainly read the reports. We'll be updated every day on what he's doing down there."