The State of Ohio State's National Championship Defense

COLUMBUS, Ohio — As Ohio State approaches the midway point of its 2015 season, one question throughout Columbus—and by extension, all of college football—persists.

What's going on with the defending national champion Buckeyes?

Yes, Ohio State remains undefeated, is still the nation's No. 1 team and could very well find itself in pole position when the first College Football Playoff rankings of the season are revealed in four weeks. On the surface, the Buckeyes seem to be right on track when it comes to defending college football's crown.

But for anyone who's watched Ohio State play and not just checked its box scores this season, a different story has begun to unfold.

Despite returning a combined 15 starters on both sides of the ball from last year's championship squad, the Buckeyes have hardly looked like the dominant force many expected them to be when when they were named college football's first-ever unanimous preseason No. 1 team in August.

Ohio State's latest close call came by way of a 34-27 escape from Bloomington, Indiana, where the Buckeyes held off a last-minute drive in regulation that could have given the Hoosiers the opportunity to pull off the upset with a two-point conversion.

"I think I've learned to enjoy it," Ohio State head coach Urban Meyer said of the win in his postgame press conference. "But I'm very frustrated."

Perhaps that's because it wasn't the first time this season the Buckeyes had found themselves on the ropes.

Darron Cummings/Associated Press

A similar situation had played out in Columbus a mere two weeks prior, with Ohio State staving off two late-fourth quarter drives from Northern Illinois in what was ultimately a 20-13 win for the Buckeyes over their opponent from the Mid-American Conference.

Ohio State's inconsistencies also showed up in a season-opening victory against Virginia Tech and a subsequent home win over Hawaii, although the lopsided final scores in each game may not have indicated as much.

So what's wrong with the 5-0 and top-ranked Buckeyes?

The majority of the answer to that question can be found on the offensive side of the ball.

Despite returning such an experienced unit, Ohio State has lost 13 turnovers through its first five games of the season, the fifth-most in all of college football. The Buckeyes currently rank 101st in the country when it comes to turnover margin (minus-four), a far cry from the No. 27 ranking Ohio State possessed in the same category a season ago when it lost 26 turnovers in 15 games.

If Meyer made one thing clear after the Buckeyes' closer-than-expected win over Indiana, it's that Ohio State must fix its turnover issue.

And sooner rather than later.

"There’s a couple ways to do it," Meyer said. "Just keep coaching, emphasizing what we do and second, if guys lay it on the ground, they just can’t play."

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Some of the Buckeyes' problems with taking care of the ball could be blamed on the quarterback battle between Cardale Jones and J.T. Barrett that lasted into the fourth week of the season and still doesn't seem to be completely settled.

Jones has been the Buckeyes' starter for the first five games but has been one of the team's biggest offenders when it's come to committing turnovers, having thrown five interceptions—including a costly pick in the third quarter against the Hoosiers.

Meyer, however, opted to keep Jones in the game rather than bench him for Barrett—as he had against Hawaii and Northern Illinois—a step forward when it comes to the OSU offense continuing to establish its identity.

It also didn't hurt that star running back Ezekiel Elliott ran for 274 yards—240 of which came in the second half—and three touchdowns against Indiana.

Elliott's breakout game Saturday marked the first time the Buckeyes offense resembled its national championship form.

As Meyer said after the game, the regular season is a process—one that won't be complete for another seven weeks.

The fourth-year Ohio State head coach even likened the Buckeyes' outing in Bloomington to a similar close call against Penn State a season ago, which saw OSU overcome its issues and escape with a victory right before hitting its stride en route to its playoff run.

"You take the three turnovers out and that’s a solid performance by the Buckeyes," Meyer said. "I didn’t say great—but a solid performance by the Buckeyes."

In order to live up to its preseason billing, however, Ohio State is going to need to do better than "solid."

Darron Cummings/Associated Press

While the Buckeyes defense has been steady—although its production may not have matched its talent against Indiana—Ohio State is going to need a complete team to come together to make the College Football Playoff for the second consecutive year.

With a three-game stretch to close the season that could include matchups against No. 4 Michigan State, No. 18 Michigan and a potential appearance in the Big Ten title game, Ohio State will have its work cut out for itself on the eve of this year's playoff selection process.

A lot of time remains between now and then, and the Buckeyes' schedule would seem to give them plenty of protection until November.

Then again, if Ohio State doesn't start taking care of the ball, that may not be the case.

"The turnovers have to change right now," Meyer said. "I mean, right now."

Ben Axelrod is Bleacher Report's Big Ten lead writer. You can follow him on Twitter @BenAxelrod. Unless noted otherwise, all quotes were obtained firsthand. All statistics courtesy of cfbstats.com. Recruiting rankings courtesy of 247Sports.