I’m not exactly sure how a position group can become as depleted as the 2009 crop of defensive backs at a place like Michigan. But it feels like this has been a long time coming. For the fans’ sake, I’ll start with the good:

Junior Donovan Warren and sophomore Boubacar Cissoko.

Say what you want about Warren — as many Michigan fans have often complained about his decision-making abilities — but he’s probably the most athletic member of the 2009 campaign.

His hip and body movements are as good as anyone in the Big Ten, and this is the year for him to prove that he can be the player everyone thought he could be. Now, with the reliable Morgan Trent gone, it’s up to Warren to anchor a defensive backfield that is in desperate need of a leader.

The DBs — especially the safety corps — are rife with inexperience and question marks, but if Warren can be that shutdown, lock-up-his-half-of-the-field guy, it’ll make it a lot easier on everyone else. Warren’s ankle bothered him pretty much all last season, but all signs point to him being ready to go in the fall.

There’s a lot of pressure on him to excel, and he’s up to it athletically. We'll have to wait and see if he can handle it mentally.

Cissoko is a great compliment to Warren’s shutdown ability. On the other side of the field, he’s a feisty, aggressive corner — an all-or-nothing type guy. Plus, he refers to himself as “Boobie” in interviews, and that’s pretty cool, too.

He’s going to press — a lot — and with another year at the collegiate level under his belt, I think he will find more success with the style. You can’t come in as a freshman and expect to hold Big Ten receivers at the line every play. But he’s stronger and wiser now, which will go a long way with his killer instincts.

Obviously, the safeties — whoever they end up being — are going to have to be aware that if Cissoko is pressing as much as he’d like to, he’s bound to get beat eventually — no matter how good he is.

Keeping with cornerbacks, the situation becomes really murky. If Warren re-tweaks his ankle or if Cissoko goes down, there is no one with any semblance of experience to step in and back them up.

Redshirt freshman J.T. Floyd is probably the third CB on the depth chart. He was a good scout teamer last season, and he impressed the coaches in the spring while Warren was out with his ankle scope. But none of that means he’s ready for the big time, and I’d be nervous putting him out there for any significant playing time just yet.

Reports say he’s not too fast, which is a problem with today’s offensive philosophies. But he just might be the best option Michigan has behind Warren and Cissoko.

Next up is freshman Justin Turner, who’s massive (6’2’’) for a cornerback. He was the No. 3 CB recruit in the nation, according to Rivals.com, but, from a coaching standpoint, I’d rather not throw a freshman right away into a position like cornerback. There’s just too big of a jump from high school wide receivers to collegiate ones.

But if the word on the street is true — and Turner seemed to back it up at the Army All-American Game — he’s a big, athletic CB who will get his fair share of playing time this season.

Either of these guys would be adequate in a pinch, but the dropoff in talent from starter to second stringer is pretty alarming. The starters are good, but what if they get hurt?

Now, for the really bad news, Michigan fans: safety.

It’s been a rough couple of years for this position. Remember all those long plays against Appalachian State and Oregon? What about Illinois from 2008? Poor tackling angles and even worse reads have come back to haunt Michigan’s safeties, who are supposed to be the last line of defense.

And it looks like it's going to be another one of those years.

Look, the coaching staff might not even know who’s going to start until Sept. 4, and it’s not really because they have a wealth of talent. Junior Troy Woolfolk is a convert from CB, and he’s likely to get a nod. He’s never really seen a lot of playing time, but he’s a smart guy. He’ll be able to pick up the position quickly enough, and I expect to see him start.

But then what?

Freshman Vladimir Emilien? Who knows? He wore a green jersey through spring, meaning he was nursing an injury and teammates should take it easy with him. That’s because he missed his senior year of high school with an ACL tear.