Ohio State's defense hit rock bottom at the end of the 2013 season, and head coach Urban Meyer knew something needed to change.
The Buckeyes defense had given up an average of 38.7 points and 539 yards to the team's final three opponents—Michigan, Michigan State and Clemson—while dropping its last two games of the year. Those losses halted a historic 24-game winning streak and cost Ohio State a chance to play Florida State in the BCS National Championship Game.
That prompted Meyer to shake things up.
After former co-defensive coordinator Everett Withers left for James Madison and former defensive line coach Mike Vrabel jumped to the NFL, Meyer wanted to find replacements who would bring the aggressiveness and spark back to Ohio State's defense.
That's what brought new co-defensive coordinator Chris Ash (formerly at Arkansas) and defensive line coach Larry Johnson (Penn State) to Columbus.
Ash was tasked with leading the charge in a defensive overhaul. Instead of running the conservative zone schemes that defenses picked apart in 2012 and 2013, Ash installed his aggressive 4-3 scheme with quarters coverage in the secondary.
The 2014 defense made a huge leap, which was instrumental in the Buckeyes' run to (and through) the first-ever College Football Playoff.
And Ash said that this year's defense is vastly improved.
"Words can't even describe how far we've come. It's a completely different unit," Ash said on Monday, according to Eric Seger of Eleven Warriors. "Each player is better, each unit is better, the overall Silver Bullet defense is better."
That's big news for the Buckeyes, who showed glimpses of dominance during their postseason run.
It started in the Big Ten title game, when the defense was facing a stiff challenge in Wisconsin's Melvin Gordon—the nation's leading rusher and eventual Heisman Trophy runner-up. The Buckeyes stepped up in a big way, holding Gordon to 76 yards on 26 carries while blanking the Badgers 59-0.
Against Alabama in the Sugar Bowl, the Buckeyes harassed quarterback Blake Sims into one of his worst performances of the year, forcing him to throw a career-high three interceptions. They also limited Amari Cooper, who finished third in the Heisman race, to his second-worst yardage output of the season as they advanced to the national title game.
Against Oregon and its brutally efficient offense, Ohio State was at its best. The Ducks came into the game averaging 47.2 points per game, but the Buckeyes held them to a season-low 20 points while effectively limiting Heisman winner Marcus Mariota.
Instead of the defense collapsing in the pivotal three-game home stretch of the season, it thrived, and the result was a national title.
"I think our defense from the last three games was the best I've ever witnessed," Meyer said, via Seger. "Obviously we had some growing pains because we grew up the secondary and changed dramatically what we were doing. Very systematic approach."
But with seven defensive starters back, those growing pains should be a thing of the past, and the Buckeyes could be primed to dominate defensively. After watching the unit falter during his first two years in Columbus, Ohio State's head coach is excited for the upcoming season.
"I love where we're at," Meyer said, via Seger.
David Regimbal is the Ohio State football Lead Writer for Bleacher Report. Follow him on Twitter @davidreg412.
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