Harvin was limited on Wednesday because of the injury. He missed time in training camp because of it, then aggravated the injury last weekend in the win over Arizona.
Frazier says Harvin saw a doctor on Thursday and X-rays showed that no ribs were broken. But the team decided to give him the day off to rest.
Antoine Winfield also missed practice with stiffness in his neck. His status for the Bears game is in doubt.