Penn State quarterback Christian Hackenberg is one of the most polarizing prospects in the 2016 NFL draft. There are evaluators who have stated that they believe Hackenberg should go in the second round of the draft. Still others have said that his performance on tape is worrying enough that he should drop further than the second tier of passers, but the tools are still clearly there for him to potentially be an NFL-caliber quarterback.

I hold a different opinion: I don't believe Christian Hackenberg should even be drafted.

That seems like hyperbole, and it is not intended to come across as a slam against a player who is working hard for his shot to play in the NFL. But the truth is that instead of hyperbole it is actually an honest assessment backed up by three years of play-by-play grading, tape study and data.

Here is why my analysis and that of the PFF team has led me to believe that Hackenberg is not a draftable prospect in this class:

Inaccuracy

There isn't a more inaccurate quarterback prospect in this draft with a reasonable chance at being drafted. Hackenberg is inaccurate at every level of the field, on all throws and against all coverages.

This season his completion percentage when adjusted for drops, spikes, etc. was 64.0 percent, which was 120th in the nation. In 2014, he was 105th. Every accuracy number you look at sees Hackenberg struggle, and the tape shows the same thing.

Even when under no pressure at all this past season, he completed just 61.9 percent of his passes. That’s the same completion percentage Cardale Jones managed on all plays, not just pressure plays, and Jones is a player whose accuracy is seen as a negative.

Hackenberg’s completion percentage under no pressure at all of 61.9 percent would only have ranked 44th in the nation, if it was his real completion percentage.

Completion percentage can be affected by many things, but if you dive a little deeper and look specifically at his ball placement, things get even worse. Hackenberg completed 192 passes this past season, but when we charted ball location for quarterbacks in this draft class, 55 of those catches were badly located passes. He was only accurate on 48.1 percent of attempts when throwing to open receivers. By comparison, Cody Kessler was accurate on 73.2 percent of his attempts to open receivers, Carson Wentz was at 61.2 percent. Even Cardale Jones, our inaccuracy comp in this exercise, was 5 percent better when throwing to open guys.

I have never seen a quarterback consistently miss as many wide receiver screens as Hackenberg. Receiver screens are supposed to be high-percentage plays. In college, the average receiver screen pass is only off-target on 4.75 percent of attempts. In the NFL that figure becomes 3.45 percent, and the worst mark any QB has posted over the past three seasons is Chad Henne, at 8.47 percent. Last season, Hackenberg was off-target on 15.8 percent of his receiver screen passes — around five times more inaccurate than the average NFL QB.

The story only gets worse on passes 11 to 20 yards down the field. He is accurate in ball-location terms on just 27.5 percent of them (the best QBs in this class are up around 50 percent). From 21 to 30, yards he is down at 12.0 percent (with the best marks around 40 percent).

Hackenberg is capable of occasionally brilliant passes, and every now and then, exceptional accuracy. But when looking at his entire body of work, our assessment is that he is far too inaccurate to play in the NFL.

Decision-making

All quarterbacks can be caught out, or baited, or somehow convinced to attempt a pass they shouldn’t, but at least an evaluator can usually work out where the play broke down and what tempted him into taking the shot. Hackenberg regularly has plays where the pass has little to no chance of succeeding, but he puts the ball in the air anyway.

That is a fatal flaw for an NFL quarterback, as QBs need to be able to read what happens before and after the snap to put the ball in the right place. Sometimes Hackenberg can do exactly that, but far too often he appears to simply decide not to, and those plays lead to simple turnovers.

PFF’s play-by-play grading scale works from minus-2 to plus-2 in 0.5 increments. Minus-1.5 and minus-2 throws are catastrophic plays that usually result in a turnover. Hackenberg has 37 of them over his college career, equivalent to a catastrophically bad pass on 3.1 percent of his attempts. Jared Goff, by contrast, threw one on 1.1 percent in 2015. Even Michigan State QB Connor Cook, whom we have noted throughout his draft evaluation for his bad habit of reckless throws, threw one on 1.5 percent — or less than half the rate of Hackenberg.

Hackenberg regularly does not see defenders breaking on the ball or cutting underneath his intended receiver. Against Temple in the first game of this season, he missed a defensive end dropping straight under a quick slant and almost tossed him a pick-six. Last year against Indiana he tossed the ball straight to a defender who was cutting in front of his bubble screen and did throw a pick-six:

Turning the ball over at the NFL level is the cardinal sin of quarterback play. Most top passers now have historically low interception and turnover rates. Hackenberg puts the ball in that kind of danger far too often, at a far lower level of competition.

Controlling pressure

Quarterbacks play a role in the rate at which they face pressure — it isn't simply a function of the offensive line. This is important to keep in mind when evaluating Hackenberg.

Many have cited Penn State's poor pass protection as a reason for Hackenberg's struggles, and to be clear, it's not as though I thought he had the benefit of a great offensive line. But let's look at the 2015 season opener against Temple as an example of how Hackenberg deserved some blame for the amount of pressure he was under.

Hackenberg was under pressure on 17 of his 36 dropbacks in that game, but only seven of those pressures were charged to the offensive line. That means nearly 60 percent of the pressure he was under in that game was not surrendered by his O-line, and much of it was clear from before the snap.

Temple regularly showed six rushers before the snap, came with all of them, and Hackenberg was surprised by the free rusher despite only having five men in the protection. Some might want to cut him a break for the free rusher the offense couldn’t pick up, but it’s his job to understand that it is coming from the pre-snap read and be prepared to get rid of the ball quickly.

Don’t get me wrong: Hackenberg’s line was not good at Penn State, but it wasn’t the prohibitive collection of uniformed turnstyles that they've been made out to be, either. As a unit they surrendered 135 total pressures in 2015, which is bad, but 15 other teams managed worse, including Goff’s California Bears (154). 45 other offensive lines surrendered pressure at a greater rate than Hackenberg’s line last season. And in 2014, we charged Hackenberg with eight of the sacks he took, which is five more than any single lineman gave up.

In fact, since he has been the quarterback, Hackenberg has been directly to blame for more sacks than any single lineman blocking for him, and that doesn’t even touch the ones he was indirectly at fault for by being unable to effectively diagnose the pressure looks he was presented with.

Lack of upside

Much of the positive buzz around Hackenberg as a prospect has to do with the fact that he looks the part of an NFL QB. But while Hackenberg can make every throw you can think of, and does have some beautiful passes in his tape, the frequency with which he is able to produce them is concerning.

In 2015, Hackenberg produced a pass graded at plus-1 or higher (a stat we have taken to calling “Big-Time Throws,” much to my distress) on 2.68 percent of his attempts. 151 QBs were better than that, and only nine were worse.

But what about 2013?

One of the narratives around Hackenberg is that his play dropped off after an impressive true freshman campaign in 2013 — when Bill O'Brien was his head coach, prior to taking over the Houston Texans' job, and his top target was Allen Robinson, now one of the league's best young wide receivers for the Jaguars — due to a subpar supporting cast and poor fit with new Penn State head coach James Franklin. It's certainly true that his raw numbers were more encouraging that season.

Unfortunately for Hackenberg, when we went back and graded his 2013 campaign, the results were not good. His 2013 season grade was a minus-24.7, which would have ranked third from the bottom in this draft class for the 2015 season.

Take a look at this table with a group of this year’s quarterbacks and their grades from the 2015 season. I have included each year of Hackenberg at the bottom. Goff leads the way in grading terms by some distance. Carson Wentz graded well, especially considering the time he missed through injury, but the bigger point is that nowhere on this list is there a prospect other than Hackenberg who graded negatively overall.

Lest you think I’m just cherry-picking prospects to ensure that result, the only quarterback prospect in this draft class (other than Hackenberg) with any kind of pro prospects whatsoever to have a negative overall grade is Ohio State's Cardale Jones, and he at least has the asterisk of only attempting 270 passes in his entire college career.

When you factor in that Hackenberg was only a true freshman, then it probably is fair to say that the 2013 season was his best — but he still earned a lower grade in that season than any QB in this current draft class, and was greatly affected by the benefit of Robinson's ability to either take routine catches to the house or go up and haul in questionable passes that were thrown as much to the defensive back as they were him.

This pass is a good example, as it was thrown straight to a corner who had position over the top and leverage on the receiver, but simply misplayed the ball in the air. Robinson, on the other hand, went up and high-pointed the ball, bringing it in for a big gain. This was a pass that ended up looking very nice based on the result, but probably shouldn’t have been thrown in the first place — even to a receiver as talented as Robinson.

Conclusion

One of the few things left supporting Hackenberg’s draft stock is that he looks like an NFL quarterback. His arm is pretty good, and he ticks most of the measurable boxes, but that’s like a newly created Madden player before you have assigned all the performance attributes like accuracy and decision-making. At that point all you have is a player shell.

While there is good to his game in small flashes, you have to overlook so much bad to see it that it simply isn’t enough. Tim Tebow made some nice throws, too, but it didn’t make him a starting NFL quarterback.

Even the best of Hackenberg is an average, inaccurate passer with a few worrying qualities. In my opinion, his NFL ceiling is as a backup a team hopes it never has to play.

There was a time when Hackenberg was largely seen as a first-round talent, and it’s taken three seasons of poor play for him to be moved down most draft boards to the Day 2 or Day 3 range. But after evaluating him on tape to go along with three seasons of play-by-play data, I can’t see the case for drafting him at all.