In his first four seasons with the Lions, quarterback Matthew Stafford has taken command of his body and health. He has learned what it takes, after two rocky seasons, to stay healthy a full season.

He also has taken command of the huddle and offense. There are no questions about who the field general is on this team.

But there is one more step Stafford needs to make, and coach Jim Schwartz and general manager Martin Mayhew have alluded to this. He needs to take command of the locker room.

"We need younger players who are developing with us to take more of a leadership role," Mayhew said in February. "Part of developing as a player is not just developing on the field, but developing leadership, locker room, off-the-field, and you start to feel a little bit more comfortable every year. We need some guys to step up that way, also."

Stafford understands he's one of those "developing" players, and he's already demonstrated he's ready to take on more responsibility inside the locker room. He stayed in Detroit the entire offseason. He was at the practice facility as much or more as any other player. He was active in helping to recruit free agents like Reggie Bush and Glover Quin.

"I think you build on your leadership every year, no matter if this is (year) 16 or whatever it is for Peyton (Manning) or if this is my fifth coming up," Stafford said Tuesday. "You know, I think you're always constantly trying to get to know the guys better, trying to push guys, trying to figure out what makes guys tick and find ways to motivate everybody."

The addition of Bush, heralded as a consummate professional and leader by coaches and teammates in Miami, certainly will bolster the leadership in the offensive room, as will the return of veteran receiver Nate Burleson.

But, Stafford knows as the franchise quarterback, he's in the ultimate leadership position.

"It's a collective effort, but I have no problem spearheading it," Stafford said. "But we need guys in all facets of our team to step up and make sure they're ready to go."