Hart, who strained the muscle during a throwing exercise a week ago, was taking fly balls when he turned to catch a ball and felt discomfort in his rib cage.
“I was hoping it would feel better than it did,” said Hart, who had been expected to miss two weeks. “It’s not getting worse, but it’s obviously not going as fast as I would like it to go. Two weeks would have been nice but I think we definitely may be a little longer. I don’t know any timetable.”
“It will be a day-to-day thing to see how much we can push him,” Roenicke said. “I still think he’s going to be ready for opening day. Even if it’s a week playing (spring) games, I think he’ll be fine.”