Bradley McDougald has been handed two of the hardest NFL tasks imaginable this season — stepping in for Seattle free safety Earl Thomas and strong safety Kam Chancellor. It was something he signed on for willingly when he agreed to a one-year deal with the Seahawks in the offseason after starting the previous two seasons with Tampa Bay and then becoming a free agent. As he said this week, his original thought was actually that the team might find ways to use him in packages where he would play with Thomas and Chancellor. “When I originally came here, I had thoughts of being on the field with Earl and Kam,” he said. “You know, finding a position out there that suited me and enabled the defense to grow.” But injuries have foiled that plan. McDougald first had to spell Thomas for two games when Thomas suffered a hamstring injury. And now he is taking the place of Chancellor for the rest of the season after Chancellor suffered a neck injury against Arizona. McDougald has started the last four games in place of Chancellor. And while no one can be Chancellor, McDougald’s play has been more than good enough — he has 34 tackles in those four games and against the Eagles got credit for shutting down tight end Zach Ertz.