Grandal took a foul tip to the mask in Friday's game and was scratched from the lineup after concussion test results weren't as reassuring as the Padres had hoped they would be.
"They basically just compare it to the ones you have taken in the past, and mine didn't come back as well as we would have liked," Grandal said. "I could have played, but the only thing they were worried about was how I would respond if I got another foul ball to the mask. We obviously didn't want to risk it."
Grandal had insisted before Saturday's game that he was ready to play and that he didn't feel he needed to be taken out of Friday's game, but said he understood the Padres' desire to side with caution.
"I totally feel safe with this team and how they take care of the players," Grandal said. "It's one of those things where you just have to take it as it comes."