Much like the wide receivers, Ohio State's linebacker unit used to be a big worry for Urban Meyer.

In fact, as the Buckeyes defense crumbled throughout the course of the 2013 season, Meyer tabbed the linebackers as his top concern, according to Kyle Rowland of Eleven Warriors.

"The linebacker position is still my biggest concern on our team," Meyer said, via Rowland. "The depth is a major concern. When you think of the great linebackers here; arguably the last decade as good a linebackers as anywhere in the country played at Ohio State."

That wasn't the case during Meyer's first two years in Columbus, but that changed in a big way last season.

Part of the credit goes to the defensive staff, headlined by co-defensive coordinators Luke Fickell and Chris Ash. The Buckeyes coaches adjusted their scheme very effectively last season—simplifying things to allow their superior athletes to thrive.

That allowed freshmen such as Darron Lee (redshirt) and Raekwon McMillan to see the field early and make a big impact.

Lee emerged as a breakout star, ranking third on the team with 81 tackles and second with 16.5 tackles for loss and 7.5 sacks. He was a force rushing the passer and proved to be the team's most instinctive player, tracking the ball with elite speed and finishing plays with his sure tackling.

Just a redshirt sophomore in 2015, Lee has all the tools to be one of the most dominant linebackers in the country.

Alongside Lee will be McMillan, who's ready to step into a primary role after splitting time with Curtis Grant at middle linebacker last year, and Joshua Perry, who was the team's leading tackler in 2014.