People look at the roster for the upcoming football season, and everybody seems to come to the same conclusion: The biggest question mark is the defensive line. It's pretty clear to see why this seems to be the consensus, as Iowa lost three of their four starters from last year's defensive line to the NFL. Between the departed Ballard, Clayborn, and Klug, Iowa loses 43.86% of their tackles for loss from last year. If you look at just the tackles for loss by the defensive line, Iowa loses 62.50% of their tackles for loss from the 2010 season.
Iowa does get back Mike Daniels, who by himself, returns 19.30% of last year's tackles for loss (27.50% of last year's defensive line tackles for loss). Broderick Binns is also a year removed from a 9.5 tackles for loss season, with 5.5 of them being sacks. However, 2010 was a gigantic step in the wrong direction, as he came away with only 1 tackle for loss and no sacks. After those two, though, Iowa has some unproven guys with limited experience. Lebron Daniel, Dominic Alvis, and Steve Bigach only return 5.26% of last year's total tackles for loss between the three of them. So, you can see why people might be a little concerned about this year's front four.
Now, Mike Daniels could tear up the Big 10 and Broderick Binns could return to 2009 form. Iowa could also have a few of the guys with a little experience step up. For instance, someone like Carl Davis, Mike Hardy, or even Darian Cooper could prove to be Big 10 ready. But, how likely is that perfect scenario to happen? Well, if you look at Iowa's recent track record at dropping their opponent behind the line of scrimmage, probably not very likely.
The chart above shows the percentage of opponent plays that went for negative yardage in a season. Iowa struggled in this category last year, taking almost four more plays than the average Big 10 team to tally a tackle for loss. However, last year wasn't an apparition. Instead, it was part of a continuing trend for the Hawkeyes.
For the past five seasons, Iowa's defense has been below the Big 10 average at dropping their opponent in the backfield. They were above average from 2003-2005, but since 2006, they have been pretty solidly below average. 2009 was a good year for the Hawkeyes, but the Big 10 had some very solid defenses that were a little better at blowing up their opponents in the backfield. When you look at the averages from 2003-2010, Iowa averages a tackle for loss on 8.28% of their opponent's plays, while the rest of the Big 10 averages 8.70%. Iowa's eight year average is good enough for a mediocre sixth in the Big 10, but that is largely held up by their above average 2003-2005 seasons. If you take their five year average, Iowa's 7.61% is dead last since 2006. Minnesota is the next worst at 7.82%, and is the only other team under 8%.
This was quite the surprise for me, considering Iowa consistently has one of the best defenses in the Big 10. In fact, since 2003, Iowa has been the third best team in the conference in yards per play allowed, percentage of opponent's plays ending in touchdowns, and percentage of opponent's plays ending in turnovers. In those first two categories, Ohio State and Penn State's defenses are the only two that have been better over that span. In the third category, Iowa is tied with Penn State, and trails only Ohio State and Wisconsin.
So, why have Iowa's recent teams struggled at getting into the backfield? That's hard to answer.
One possibility (and there are probably many), could be the spread passing attack. Team's like Northwestern and Indiana can give Iowa's defenses problems, three-step dropping and dinking and dunking the ball down the field. The quick passing game allows the ball to get out before the defense can get to the quarterback. It also lets opposing teams leave less guys in to block, and therefore, leaves the defense with more guys to cover. The spread offense is more prevalent than ever before, and Iowa seems to be trying to adjust this year. It's yet to be seen, however, if smaller, quicker linebackers will help alleviate the spread attack headache, or if they become a liability in the run game.
Transitioning this back to the upcoming season, what does this mean for 2011? Does it mean anything? Well, no. Not necessarily. This is far from predictive, and it's not like being below average in tackles for loss makes a defense inevitably bad. The 2009 team was below average in this category, but were dominant in every other facet of destroying their opponent. Unfortunatley, though, this trend doesn't make Hawkeyes fans feel any more optimistic about this year's defensive line.
In 2011, the pressure is on Mike Daniels, who certainly has shown that he can be a handful for opposing teams. But, 7.5 of his 11 tackles for loss came during Iowa's non-conference schedule last year. Granted, he did have 2 tackles for loss against Arizona, but he also got 4 of his 11 versus a Ball State team that wasn't exactly a MAC powerhouse.
After Daniels, Broderick Binns really needs to fix whatever was ailing him the previous year. I don't know what happened to him, but let's hope his Senior year ends with more of a bang, than the fizzle of his Junior year.
Overall, I'm cautiously optimistic about Iowa's chances this year, but the defensive line still bothers me. I'm hoping for a freshman to step up and prove they are ready, just like Clayborn and Ballard did in 2007 and King and Kroul did in 2005. Whether that is a red-shirt freshman like Carl Davis or a true freshman like Darian Cooper. But, it still remains to be seen. I wouldn't put money on this being the year that Iowa gets back to above average in the tackles for loss category. However, I wouldn't rule out them having a solid defense. They are just going to need unproven guys to step up on the defensive line.