On Thursday night, Mariners manager Eric Wedge gave Morse a night off, starting Jason Bay in left field and recent callup Carlos Peguero in right.
"We felt like from yesterday morning to tomorrow night is the greatest amount of time we can give him to try to help it improve," Wedge said. "He still feels it, but it's improving. It's going to take some time."
Morse pointed out that he usually begins seasons slowly. This year, he's already got six home runs and 10 RBIs.
"I already have career records in April for everything I've done," Morse said with a smile. "I look at it like I'm having a good April."
Doug Miller is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.