Reaffirming the suspicions of attentive fans, Dodgers catcher Yasmani Grandal's left shoulder injury has flared up again, and he is headed for an MRI exam to try to sort out what's going on.

Grandal was held out of the lineup on Monday after his shoulder flared up while he was taking batting practice before the game, manager Don Mattingly said.

Mattingly was unsure as to whether Grandal had been concealing his pain since returning to the team after being struck by a foul ball on his left shoulder in Philadelphia in early August, or whether the injury had suddenly flared up.

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"This is in the same area," Mattingly said. "I don't know if he was not being totally honest with us as far as dealing with that pain, or just didn't want to say. I mean, some guys are just not going to tell you."

Grandal was in the midst of a career year at the plate heading into August. However, since sustaining the injury, the 26-year-old catcher has hit .055/.212/.055 with no home runs, two RBI, three hits, and 21 strikeouts in 66 plate appearances over 18 games.

He is now hitting .253/.367/.434, a significant drop from where he was exactly a month ago: .287/.391/.500.

The Los Angeles Times reports that Grandal declined to comment on the matter.

(h/t Los Angeles Times)