Miguel Cairo started in Phillips' place and batted seventh. Third baseman Scott Rolen moved up to Phillips' fourth spot in the batting order.
Phillips left Wednesday's game before the sixth inning after feeling dizzy. In the third inning, he took a shot to the head as Aramis Ramirez was caught stealing at second base.
Just after arriving to AT&T Park, Phillips went to the batting cage to take some swings. After returning to the clubhouse, he and head trainer Paul Lessard went into manager Dusty Baker's office for a meeting.
When asked how the hitting in the cage went, Phillips chuckled at first.
"It went OK," Phillips replied.
Before it was decided whether or not Phillips could play, he took some ground balls on the field.
Baker felt that Phillips needed to be better than just OK to play.
"Definitely, especially here in this twilight and especially with these hard throwers they've got here," said Baker before his decision was made. "If you lose any kind of vision or blink out for a second, you can get hit upside the head with a 95 [mph pitch]. He has to feel better to play. We've got [Matt] Cain tomorrow, who throws about a thousand [mph]."
Asked whether he was concerned about whether his injury was a concussion, Phillips couldn't say.
"That word came up yesterday. It's the last thing I'm trying to think about," he said before the decision was made. "I'm trying to stay positive. I never felt like this before. The only thing I can really say is it's my birthday and I'm really happy.
"I looked at the play a little bit and can't believe I felt like that after that play. He hit me kind of square on."