You'll get a ticket for nearly every game despite of the derby.
Just visit the stadium for making new friends.As i know,away games are shown normallx at the viola pub,directly at tve stadium. Try it there.
Feel free to come to the stadium on sunday. If you're early enough in front of the osttribüne,maybe you can buy a ticket from somebody holding it up. Otherwise,drink a beer at vioma pub,you don't need a ticket to enter before the match starts.
Bist deppert mit dem Handy heute in der Sonne - gar net amal so guat