‘Dolphins strong safety Brian Walker smiles at this topic. He’s been having to prove his toughness since he came into the league in 1996 as an undrafted 186-pound cornerback. It didn’t change this season when the 206-pounder was asked to switch from free safety. "My job is all about banging," Walker said. "Back there at free safety, you didn’t have to worry about going against the tight ends and pulling guards because those big guys don’t want to run downfield that far. I know I’ve got to play a physical game."’