Believe it or not, the Lions took a step forward last season on defense. And it was a pretty big one, too.

The Lions went from allowing 367.6 yards and ranking 23rd in the NFL in 2011 to allowing 341.1 yards and ranking 13th in 2012.

Not coincidentally, the Lions returned 11 starters on defense in 2012. That continuity helped communication and production.

But this season the Lions will have at least three new starters and possibly four, depending on who plays cornerback opposite Chris Houston.

Even with the turnover, middle linebacker Stephen Tulloch doesn't view 2013 as a transition year for the defense.

"No. Like I said, I've always been a fan of Kyle (Vanden Bosch)," he said. "He's one of the players I've always looked up to since I came in the league in '06, and the way he worked. He laid the groundwork. When they brought him over here from Tennessee, he brought a sense of urgency and I think guys understand that, a young guy like Willie (Young). And everybody else, we feed on that.

"I think the pieces are there. We'll be fine and move forward. And I'm telling you, this team is heading in the right direction and, like I said, I'm excited about that."