Brent Yarina, BTN.com Senior Editor, October 16, 2013

So, here we are at the midway point of the 2013 Big Ten football season, and I can't help but wonder which Big Ten title contender has the most to prove in the second half. Is it Ohio State, the undefeated team that hasn't lost since the 2012 Gator Bowl? Is it Michigan, the 5-1 team that squeaked past Akron and UConn? Is it Nebraska, the 5-1 team that lost its lone true test? Or is it someone else?

I say it's Nebraska. The Huskers, my preseason Legends Division favorite, are 5-1. But, really, what do we know about them? They looked terrible against UCLA, their lone true test, and their defense still gives up too many yards, too many big plays, too many points.

No, I'm not ready to trust this defense after it limited inferior Illinois and vastly inferior Purdue to an aggregate 26 points the last two weeks. Simply put, those teams are going to struggle to score in the Big Ten. We won't know anything about this unit for a couple weeks, when it opens a tough four-game stretch vs. Northwestern, at Michigan, vs. Michigan State and at Penn State.

"I still like the potential of this group," Bo Pelini said of his defense.

Defense and the lack of a quality win, however, aren't the only issues the Huskers must overcome. Star quarterback Taylor Martinez is battling turf toe and hasn't played in a month, while stud offensive lineman Spencer Long could be lost for the year due to a left knee injury.

Any way one looks at the Huskers six games in, there's a lot of uncertainty, a lot of things to prove. We'll know a lot more about this team in the coming weeks.

Here's who Big Ten fans said has the most to prove:

About Brent Yarina BTN.com senior editor Brent Yarina covers football and men's basketball for BTN.com. He writes the popular uniform feature "Clothes Call," which also focuses on the latest cosmetic changes across Big Ten arenas and stadiums. Read all of his work here. You can subscribe to Yarina's RSS feed and follow him on Twitter @BTNBrentYarina.