This is an example of an illegal back screen. This screen is set outside the vision of the defender thus the principles of time and distance apply. The principles of time and distance state that a player cannot take a position so near/ and or so quickly in the path of a moving opponent that the latter does not have sufficient time or distance either to stop or change direction. In this example White 13 sets a back screen on Orange 5. Although he is stationary at the point of contact, he does not give Orange 5 sufficient time and distance to avoid contact. This is an illegal screen committed by White 13.