Star player menu will open after you complete certain tutorial task.
You can select three (3) 15 year old juniors to train as a star player
Star players will earn bonus sponsors according to their talent and they play 10% better than a normal player
Star players can be sold but if they are under the average of 50 when they are put in to the transferlist they
will lose thei "star" status. So basicly you can have more then three star players but you can only train new
one if you have less then three of them.
... And of course I will start punishing those as they make nicer targets