While most people are familiar with the phrase "red-shirt" most people have no idea what a grey-shirt is. In fact, the NCAA does not even acknowledge the term.
Here is how grey-shirting works:
Grey-shirting is a way for schools to skate around the recruiting rules. It allows schools to over-sign, regardless of how many prospects they signed the previous year.
- A player commits to a team that is over-signed.
- That player either doesn't go to school in the fall, or enrolls part-time and pays their own way. They are not officially on the team.
- In January of the following year, that player enrolls full-time and officially joins the team. They are technically part of the recruiting class for the following year.
Every player has a five year window to play four seasons. That window starts the second a player is enrolled in college full-time or are on scholarship. Since the player is not enrolled full time and is not on scholarship, their "NCAA clock" has not started.
Once they join a team, they still have the full five year window and the ability to red-shirt if they so choose.
While grey-shirting, players are not on the team.
They can not practice or condition with the team. They can not be given any advantage not extended to the normal student body. Grey-shirts are not allowed at team meetings or functions either. For all intents they are essentially, regular students.