He will be reevaluated on Sunday in Cincinnati, where the team has a concussion specialist it trusts.
Asked if Rolen would be able to join the Reds at some point during their road series against the Cardinals in St. Louis from Monday through Wednesday, manager Dusty Baker said, "I'm sure he wants to."
Whether he will remains to be seen.
Rolen was hit in the head by a Jason Marquis pitch on Sunday. He returned to action by homering on Wednesday and going 1-for-5 and scoring twice in Friday's win over the Giants. Baker said Rolen didn't feel entirely right after the game.
The Reds acquired Rolen, who is signed through the 2010 season, from the Toronto Blue Jays in a four-player deal minutes before the July 31 non-waiver Trade Deadline.
Rosales, who has made 15 starts at the hot corner this season, will see an increase in his at-bats while Rolen is out. Rosales went 1-for-3 on Saturday.
Andrew Pentis is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.