Grandal said he could have stayed in the game and was evaluated by the team's athletic training staff, but manager Bud Black said before Saturday's game he wouldn't make a final decision on Grandal's status until after batting practice.
"He's feeling better but we'll see," Black said. "I'm going to let him go through [warmups] and see how he feels. We could change it; I want to make sure that he feels good."
Grandal was replaced by John Baker in the lineup, which marked Baker's 50th start behind the plate for the Padres this season. Baker has been joined by Nick Hundley (56) and Grandal (44) in giving Padres three catchers who have made at least 40 starts for the first time since 1993. No Padres team has had three catchers make 50 or more starts.
"I'm in the lineup and I came in here expecting to play," Grandal said before BP. "I told [Black] last night that I didn't have to come out, but it was just a precaution thing. I'm expecting to go back out there tonight."
Referencing his mask from last year that had four dents in the first half of the season from foul tips as an indicator of the grueling nature of the position, Grandal has been impressed with the Giants' Buster Posey, who is in contention for both the National League batting title and MVP award while being the Giants' starting catcher.
"I played against him when I was in college and he was doing it there," Grandal said. "He just has an ability to keep on being consistent, and that's why he's one of the best players in the game."