Endy Chavez lead off off and played left field in place of Reimold, who's now been out of the starting lineup for the past three games. He last started in the opener of the Angels series in Anaheim on Friday night.
Showalter said this has been a struggle for Reimold, but he's still considered day to day.
"He's getting a little better, little by little," Showalter said. "Playing has set him back. He's OK for maybe half to three-fourths of the game, and then as the game goes on, it gets worse. We're trying to resolve it completely, so the game doesn't set him back to square one."
Showalter said that, in an emergency, he probably could have used Reimold. But the Orioles are trying to be careful with the situation.
Reimold has gotten off to a hot start. He's been batting leadoff and has a .370 average with five homers and 10 RBIs in just 11 games.