All three are in play for the Buckeyes, though a fourth might have the biggest impact: Growing up.
The 2018 Ohio State was talented but young.
The former is pretty much always true while the latter tends to be every other year or so in college football, where most of the best players go pro early and everyone runs out of eligibility eventually.
Ohio State has proven able to overcome early entries into the NFL Draft in the past, but the 2018 season was the third in a row in which 75 percent of the starting defensive backs had to be replaced.
Stacking those years of losses on top of each other may have finally caught up with the Buckeyes, especially when they lost not just three members of the secondary to the pros but also five defensive linemen and two linebackers.
To see just how young the Buckeyes were, we compared starting lineups from the seven seasons of the Urban Meyer era.
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By applying a point value for each class (1.0 for true freshmen, 1.5 for redshirt freshmen, 2.0 for true sophomores and so on), we came up with an idea.
The average age score for the first six seasons was 34.5, but year seven (last season) checked in at just 31.5.
That was the lowest of the Meyer era, but just barely.
The 2013 and ’14 groups both had scores of 32.
Perhaps not coincidentally, the three youngest defenses of the Meyer era scored the lowest in defensive S&P+, an advanced metric from FootballOutsiders.com that is similar to OPS (on-base plus slugging percentage) in baseball.
As OPS measures how often a player gets on base and how far that player gets when they do (slugging), S&P+ measures success rate (how often a play gains five yards on first down, half the remaining yardage to gain on second down and all remaining yardage to gain on third down) and explosiveness (via the percentage of available yards gained based on field position).
While the 2018 group ranked 26th nationally, the ’13 squad checked in at 44th.
Although the ’14 defense was part of a national championship season, it struggled mightily early in the year and ended up 24th in S&P+ when all the games were put together.
Meanwhile, the more experienced groups of 2015, ’16 and ’17 respectively ranked sixth, eighth and seventh in the nation overall according to the advanced numbers.
Knowing that, how do things look for the 2019 Ohio State defense?
There is some uncertainty about who will be in the No. 1 unit when the Buckeyes take the field against Florida Atlantic, but if the 10 returning players who were starters at the end of last season retain their positions this fall, Ohio State could have the oldest defense it has fielded in nearly 15 years.
The age score for the ’19 group is 41 with fifth-year senior Jashon Cornell penciled in as Dre’Mont Jones’ replacement at defensive tackle.
If that job goes to junior Haskell Garrett, the score of 39.5 would still rank No. 3 since at least 2001, trailing only 2009 (40) and 2005 (42). Even if a sophomore wins the job, the ’19 defense would still be the oldest since 2012.
Count Jeff Hafley, who arrived in January as co-defensive coordinator, among the optimistic.
Although he said he is not holding anything his new players have done in the past against them, he liked what he saw in the spring.
“I gave guys a clean slate,” Hafley said. “We started the workouts and the mat drills and then we got to some fundamental drills and then we got to spring football. I kind of went from there and am very excited. They have done a great job recruiting here, they really have.
“Whether it is a four-star, five-star, three-star (recruit), they have got good players, and I and very grateful for that. I am excited to coach those guys. I can’t wait for training camp, I am excited to go on vacation too, for my wife’s sake. But I can’t wait for training camp, I can’t get enough of it right now.”