I have read that Rondo called and spoke with Adrian Peterson regarding his injury and rehab because they were extremely similar injuries. Peterson injured his knee in Dec. 2011 and by August 2012 was dominating in football.
This injury(an ACL tear alone) is no longer a year injury for athletes. Its getting to be a 7-9 month injury, dependent on the athletes toleration of pain during rehab. Rondo once played a game with a separated elbow. I think his pain toleration level is fairly high.
BC is right. Rondo, who was reported doing two-a-days and running over a month ago, will be ready by season's start. The Celtics have already said they expect him back by then.