Michigan senior strong safety Jordan Kovacs had 75 tackles, four sacks, one interception and two forced fumbles last season for the Wolverines.

A year ago, the answer was simple.

When spring camp opened, the Michigan football team had two clear leaders on defense in senior linemen Mike Martin and Ryan Van Bergen.

This spring, Martin and Van Bergen are busy preparing for the NFL Draft, leaving the door open for new voices to emerge inside the defensive huddle.

Of those voices, one isn't a surprise. The other is, though.

"Defensively, (senior safety Jordan) Kovacs is a guy who shows a great deal of leadership," Michigan coach Brady Hoke said. "And I think Will (Campbell) is trying to step up as a leader."

Kovacs' ascension to a more concrete leader on defense almost seems natural.

Arguably the team's most productive defensive back when healthy, the former walk-on was a vocal presence for the Wolverines last season. His 75 tackles, four sacks, one interception and two forced fumbles didn't hurt either.

The anchor of a secondary that returns intact this season, Kovacs said his new role as elder statesmen just seems second nature at this point.

"After being four years in the defense and on this team, I think it's something that's starting to come naturally," Kovacs said. "We've got a lot of seniors stepping into that role, and our senior leadership is going to be huge."

Of those seniors, Hoke mentioned other natural voices, such as inside linebacker Kenny Demens and defensive end Craig Roh.

Michigan defensive lineman Will Campbell has impressed coach Brady Hoke with his attitude this spring and has shown accountability for his actions on the field.

Melanie Maxwell | AnnArbor.com

But Campbell, a player who has struggled with consistency during his career, unexpectedly has emerged as a leader.

Kovacs said Campbell routinely leads meetings off the field for the defensive linemen and also has been integral in gathering teammates for extra film sessions.

More than that, though, Hoke says the 335-pound defensive lineman has led by example, showing an accountability for his actions on the field.

"There's so much more that we can get from him," Hoke said. "But what I like about him is his attitude.

"We do some winners and losers (drills) every day during practice. It pays to be a winner, and if you lose, there's consequences. And defensively, we've had a couple consequences, and he's done a great job of (accepting them)."

Michigan won't officially name captains for the 2012 team until the fall, but defensively this spring, there seems to be more than enough self-supervision to go around.

"I'm going to have the same defense for two years in a row; I don't think I've had that in my four years here," Kovacs said. "We bring a lot of defensive players back and a lot of seniors back.

"And that's good for us. It's nice to be comfortable with the guys and be comfortable with the plays. I look forward to this season (because of) that."

Nick Baumgardner covers Michigan sports for AnnArbor.com. He can be reached at 734-623-2514, by email at nickbaumgardner@annarbor.com and followed on Twitter @nickbaumgardner.