Stage Two is skating with the Penguins in their daily practices, doing non-contact drills, getting used to skating in and around 20 bodies and participating in legit NHL-calibre workouts with speed and tempo.
Stage Three, the final test if you will, is taking contact in full practice, basically simulating game conditions to see if there's any adverse reaction to hitting or being hit.
There's no way of knowing how long each stage will take but logic would suggest that more than a few days, maybe as much as a week or more, will be required for each of the two remaining stages… and that's if there are no setbacks, which is always a possibility.
Crosby must still get clearance from doctors to resume playing. The next thing to watch for is how he handles practices, including contact.
The Penguins remain cautiously optimistic Crosby will play in the Stanley Cup playoffs.