"Chris strained his left shoulder during batting practice and didn't like the way he felt afterward, and [we] decided it would be best to scratch him," Showalter said. "He's had some history of some challenges in that area. He's got some experience with it, so we'll see how it feels tomorrow. I'm hoping that it feels a lot better, but we're going to kind of lean on him because he's got a lot of experience with what it feels like when it's not right."
Dickerson said he had a problem with his left shoulder in 2004, and he's also had more serious troubles with his right shoulder.
"Hopefully, fingers crossed, it's not that bad," Dickerson said. "I'd like to say it's pretty simple, but you never know with rotator cuffs, they're pesky. We'll see what happens tomorrow. I'm just looking forward to getting past this, and hopefully it's quicker than expected and I can get back in the lineup."
Dickerson said he injured the shoulder on the last swing of his first round of batting practice. He added that he actually drove it out for a home run, but something didn't feel right after the swing.
"It was kind of like this radiating pain. I didn't really think anything of it besides 'Ouch,'" Dickerson said.
Dickerson took the next round off, but then finished up batting practice as usual.
"I finished BP, it wasn't anything that was debilitating as far as swinging the bat, but it was definitely painful," Dickerson said. "When it was warm, it wasn't that bad. But as it was iced, it definitely was stiffer and a little bit more painful. But it's a waiting game and we're going to remain positive about it. I'm not too worried about it as long as it's not a full tear like my right shoulder."
Brittany Ghiroli is a reporter for MLB.com. Read her blog, Britt's Bird Watch, and follow her on Twitter @britt_ghiroli. Derek Wetmore is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.