COLUMBUS, Ohio (AP) -- A year ago, Ohio State's coaches were driven to distraction by defenders unable to wrap up and make a stop in the open field.
A ball carrier would be trapped near the line of scrimmage and the next thing anyone knew, he was 40 yards away in the end zone.
''The thing that I always look at is effort,'' coach Urban Meyer said. ''I felt like at one time last year there was a bad-effort issue.''
Even though the fourth-ranked Buckeyes still aren't perfect in that regard, they feel they've made remarkable improvement from 2012.
It's the nature of offenses these days to isolate a receiver or runner out by himself so he only has one defender to elude.
''Everybody is going to force you to tackle in space,'' defensive line coach Mike Vrabel said. ''That's what happens in the National Football League; it happens in college. It's easy to tackle a guy (at the line). But when you get players that are displaced and you get receivers that are split out, the space between defenders gets further and further.''
The coaching staff determined that the Buckeyes missed 16 tackles last Saturday at California - the goal is a single-digit total. Yet it's hard to argue with a 52-34 win, forcing two turnovers and a 3-0 record.
By most measures - except maybe the missed-tackles tote board - the defense has more than met expectations this year while replacing seven starters, including all four linemen.
''I'd say I'm pleased. At one point we've had 10 new starters on the field,'' Meyer said during preparations for Saturday's game against Florida A&M.
Ryan Shazier is the fulcrum of the Buckeyes' defense. An All-Big Ten performer last year, he led the team in tackles by a wide margin with 115, in tackles for a loss with 17 and was second in sacks with five.
Yet his exuberance on the field sometimes hurt him and his teammates. He'd overcommit on a tackle instead of simply hanging on until help arrived. The result was big-gainers.
''Remember, last year (Shazier) was a big culprit,'' Meyer said. ''He would overrun (a play) and they were cutting back on it.''
Through three games a year ago, the Buckeyes had been gashed for 12 plays of 20 yards or longer. This year the number's down to eight, and three of those are on kick returns.
Shazier, along with everybody else, has cleaned up his act.
''Last year when we missed tackles, we didn't have leverage on the ball,'' Shazier said. ''This year we have leverage on the ball and guys are taking shots.''
Some will look at the stats and say Ohio State's defense remains vulnerable. After all, it is surrendering 20 points and 347 yards a game.
But when you consider that only one of the front seven players on the unit (Shazier) is back, it's been a successful learning experience.
''We're playing all right,'' senior safety C.J. Barnett said. ''Cal did some things, they schemed us. But we missed too many tackles and had some lapses in coverages. But we're working on it. Hopefully we get better as the season goes on.''
Several linemen - Michael Bennett, Chris Carter and freshman Joey Bosa - have been revelations.
But the defense is still a work in progress. Linemen Adolphus Washington (groin) and Tommy Schutt (broken foot) are out. The linebacker corps is thin.
''There's some misses at recruiting at linebacker,'' Meyer said. ''Call it what it is but at linebacker we should have more depth and more experience than we have. For whatever reason, injuries and things happen, but we should be better at linebacker. That's the one concerning position right now.''
Barnett acknowledges that the Buckeyes still make mistakes and miss tackles. But that's just a way of gauging how far they have to go.
''We understand what we need to work on. It's no secret,'' he said. ''We have aspirations to be the best.''
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