College basketball this season is a tall tree that has been topped, its highest branches chopped into a brush haircut. Everywhere you look, teams that once reached for the stars have been trimmed to size.

Just when a team begins to look dominant, whack, down it comes. Almost every national contender has toppled, often inexplicably. Duke. West Virginia. Kansas. On it goes. But perhaps no team has crashed farther and faster than Ohio State, which four weeks after being 11-1 and ranked No. 2 in the nation is now 12-7 and 2-6 in the Big Ten. Timberrrrrr.

What happened? The Buckeyes turned soft. Or maybe they were soft all along. To hear coach Chris Holtmann tell it, Ohio State might have lacked toughness from the get-go. He hinted Wednesday that his players were not challenged enough during the nonconference schedule to know whether they would hold up mentally and physically in Big Ten play.

“Right now it’s a question we have to get answered,” Holtmann said.

After a 62-59 loss Thursday night to Minnesota — OSU’s sixth “L” in seven games — the answer remains elusive. At times, Ohio State appeared the tougher team, but sustaining it is the issue.

“We took a step forward,” Holtmann said Thursday of his team’s toughness. “We’ll see if we can be consistent with that.”

It’s not that the Buckeyes allowed an 11-point first-half lead to evaporate — the Golden Gophers (11-8, 5-4) are too talented not to have made a push — but how they responded to Minnesota’s run.

“I didn’t think we were as attacking or as aggressive (in the second half),” Holtmann said.

Individually, players went hard. Kyle Young scored 14 points and grabbed six rebounds despite being just three weeks into a six-week recovery from an appendectomy. But collectively there remains work to be done.

Few things sting more in sports than to be labeled soft. Cheater is worse. Quitter is up there. But to lack toughness is to fail as a competitor.

Does that describe Ohio State? Over the past month, yes. Particularly galling was a 90-76 loss Saturday at Penn State. By the end, Ohio State’s defense resembled a Mayan sacrifice victim: No heart. Quite a contrast to five weeks ago, when the Buckeyes ranked third nationally in defensive efficiency, per teamrankings.com. Entering Thursday, they ranked 22nd.

“We were a really tough team in the beginning, and it showed in our defensive numbers. But now we’ve lost the identity of toughness,” freshman guard D.J. Carton said this week.

That’s a problem, because toughness does not arrive like a package on the doorstep. “Oh, look, my toughness got delivered today.”

“The only way to get tougher is you do tough things on a regular basis,” Holtmann said.

Even then, nothing is guaranteed. As Holtmann pointed out — and this is where Buckeyes fans might want to swallow hard — toughness often is a case of nature over nurture.

“Some groups have just naturally tougher-minded guys,” Holtmann said.

Is this group naturally tough-minded? And where does coaching fit in? Given that toughness typically grows from within — meaning that no amount of tough-love coaching can turn a soft-serve athlete into a hand-dipped competitor — it falls on the coach to play the toughest hombres, even if they may not be the most skilled.

“I think we’ve got a competitive group. What I’ve got to do as a coach is figure out who our toughest guys are and roll with those,” Holtmann said. “And the other ones are going to have to learn in practice before they can play.”

Ohio State remains smack dab in the middle of adversity, which requires perseverance, which can build toughness. Or reveal a lack of it.

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