Defence and center in the defensive zone 

One D checking the puck carrier
Other D protecting the front of the net
- identify who you are supposed to be checking from the other team, and stay between them and your net
Center job is to help and support in between the two defenders
- Center can step in to help steal the puck at anytime
- Center has to be aware of un covered forwards on the other team. Try to stay between them and your net as much as possible
When in doubt, protect the house!