The strong safety tends to be somewhat larger and stronger than the free safety. However, the word strong is used because he is assigned to cover the "strong side" of the offense, the side on which the big, powerful tight end lines up on offensive plays. The strong safety tends to play closer to the line and assist in stopping the run. He may also be responsible for covering a player, such as a running back or fullback or H-back, who comes out of the backfield to receive a pass. A strong safety's duties are a hybrid of those belonging to a linebacker and those of the other defensive backs, in that he both covers the pass and stops the run. Two of the most notable retired strong safeties are Ken Houston and John Lynch. Among the best active strong safeties are Troy Polamalu and Adrian Wilson.