"He was unavailable," manager Don Mattingly said after Sunday's game. "He tried to swing early in the day and wasn't able to do it. I don't know where we'll be [Monday] with that."
Ethier is hitting .229 with four homers and 15 RBIs through 59 games. The former All-Star has a .348 slugging percentage and is reaching base at a .316 clip.
"He just hasn't been as consistent as we're used to seeing out of him and I know that concerns him, and concerns us also," Mattingly said. "We're trying to get him back to his old self."
With Hanley Ramirez out and outfielders Matt Kemp and Carl Crawford also sidelined by hamstring issues, Mattingly had rookie Scott Van Slyke as the cleanup hitter and Luis Cruz, hitting .136, behind him.
"They're definitely not the guys we were counting on coming out of Spring Training," the manager said. "It's frustrating when your middle- [of-the-order] guys are out."
Van Slyke went 0-for-4 and left six on base Sunday. Cruz struck out with the bases loaded in the first inning and finished 1-for-4 with a double.
Austin Laymance is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.