"As he went to hit today, his shoulder was bothering him. It's something that crept back up on him," Mattingly said. "It's a little more [concerning] now than before because it bounced back on him. It worries me a little."
This could explain Grandal's recent trouble at the plate. He's in a 0-for-33 slump and his batting average has dropped from .289 on Aug. 9 to .253. Mattingly had previously said Grandal was feeling fine, but Monday admitted that Grandal might not have been completely forthcoming when asked about his health.
"This is in the same area, so I don't know if he was being totally honest with us about feeling nothing or just didn't want to say. Some guys aren't going to tell you," Mattingly said.
Rollins hurt his knuckle sliding into a base in Sunday's 5-1 win over the Padres. Mattingly said he doesn't expect Rollins to miss more than a day or two.
"He told me after the game yesterday and again today, so we felt like we needed to be a little safe with it," Mattingly said. "The X-rays are to rule things out and make sure he hasn't done anything."
Howie Kendrick is still at a plateau in his rehab, as he remains unable to run at full speed. The veteran second baseman is recovering from a left hamstring strain that has held him out of the lineup since Aug. 10.
"I'm waiting just like everyone else," Kendrick said. "Game speed is going to be a lot different than practice. If I can feel it slightly in practice, it's going to be worse in the game."
Kendrick rejoined the Dodgers on Monday after doing rehab at the Dodgers extended spring training facility in Arizona. Kendrick will continue with his rehab with the team and neither Kendrick nor Mattingly has a timetable for his return.
Steve Bourbon is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.