Colin Kaepernick is going to be without his No. 1 receiver for a significant portion of training camp.
The good news is that Crabtree's issue is not foot or Achilles related, Harbaugh said. NFL Media Insider Ian Rapoport, citing a source who has spoken to Crabtree, reported that the receiver is nursing a sore hamstring and should be back within two weeks.
The 49ers haven't always been realistic about injury timetables under Harbaugh. As long as Crabtree is back on the field in time for the third preseason game, it's reasonable to expect him to be at full speed for the season opener.