"We decided to rest his legs a little bit," Harbaugh said after Thursday's practice. "He'd been going pretty hard. Whether he'll play in a game, we'll just decide and see how he feels. But there is no injury involved."
This is the second straight day that Daniels has missed. He participated in the walk-through Thursday but he sat out the practice.
Daniels has lacked explosion in training camp, and he was stripped twice on the first day of full contact.
He signed a bargain one-year, $1 million deal in free agency. He didn't command much interest (he signed almost a month into free agency) because he was limited to five games last season (broken leg) and he turns 32 during the season.
With Daniels out, rookie third-round pick Crockett Gillmore has received increased playing time.