In the second half against the Houston Rockets, the Celtics made the decision that they wanted to make the opposing 3 man have to defend a ball screen which is not done very often. Because this is an action that is not used often, players are not comfortable defending it and sometimes do not even know exactly how to defend this action. One challenge of this play is having a strong enough PG to be able to handle the pressure of a possible trap are strong defensive wing.