Could cornerback be Spartans' Achilles' heel?

One of the major keys to Michigan State's outstanding run of dominant defenses has been cornerback play.

The Spartans could count on dominant, shut-down corners to control opponents' passing games, allowing them to bring more defenders into the box to stuff the run. The coaching staff has done an excellent job of scouting and recruiting players at that position, leading to back-to-back first-round NFL draft picks in Darqueze Dennard and Trae Waynes.

But heading into the 2015 season, the "No Fly Zone" has no clear answers yet at cornerback. And the situation has been further clouded by this weekend's revelation that Darian Hicks could miss three to five weeks because of mononucleosis.

Hicks, a junior, had an up-and-down 2014 season and was replaced late in the year by Tony Lippett. But he did start 10 games and is the most experienced corner on Michigan State's roster. With him out of the mix right now, the top candidates to start appear to be junior Demetrious Cox and senior Arjen Colquhoun. Junior Jermaine Edmondson is in the mix as well. Then there are five freshmen -- redshirt Vayante Copeland and true frosh Josh Butler, Kaleel Gaines, David Dowell and Tyson Smith -- who also will have a chance to compete for playing time and possibly a starting job.

Cox definitely will play, but head coach Mark Dantonio has said that the talented junior would get looks at safety as well this preseason. If Hicks is out for a full five weeks, that would put the timeline for his return right around the Oregon game. Michigan State might have to break in some younger players, at least in the rotation, early in the season.

Learning on the fly on the back end of the defense can be a scary proposition, especially for a system such as Michigan State's that often asks its defensive backs to be on an island. The new starting corners likely will get tested right out of the gate by Western Michigan, which ranked 34th in the FBS in passing yards per game and sixth nationally in pass efficiency last season. Then comes Oregon; the Ducks might not be quite as explosive without Marcus Mariota, but they surely will still boast plenty of big-play potential.

The rest of the Spartans' defense seems fairly set, with Dantonio comparing the deep bench of talent on the defensive line with the 2002 Ohio State national champions. Ed Davis leads a solid linebacker crew, and rising star Montae Nicholson heads the safety group. It's the corners that have to prove themselves this August and beyond.

We know this: Dantonio won't hesitate to throw a rookie into the fire if the upside is there. He's done that before, most recently with Dennard, who started two games as a true freshman in 2010. You have to trust this staff's ability to evaluate cornerback skills in recruiting after they plucked Dennard and Waynes out of relative obscurity and made them stars. Dantonio, a former defensive backs coach, and co-defensive coordinator Harlon Barnett are the best in the business at developing that position.

So while there's concern here, it's not at a crisis level by any means. Still, the cornerback position bears intense scrutiny this month and early in the season because any hiccups there could derail the Spartans' championship hopes.