The Draft Research Project: Defensive Players by Position and Round

With over two thousand draft selections considered over eight years (each tracked for their first five seasons), the Draft Research Project gives a pretty good snapshot of the ranges of outcomes that happened in the draft. While not predictive, it is certainly indicative of trends that did happen and probably also trends that are likely to continue. Probably the single biggest limitation in my own data classification has been the absolute difficulty of categorizing defensive players. Players listed as linebacker at the time of the draft (sometimes with or without other adjectives) have ended up playing positions ranging from edge rusher to interior defensive line to safety–in addition to the ones who played the part of off-the-ball linebacker. The defensive line position is a mess as well. Defensive backs can mean almost any position in the secondary, but at least a few times also meant “linebacker”.

This year, I did my best to clean that up, cross-checking positions with contract data to come up with five categories. Edge rushers, defensive linemen, linebackers, safeties, and cornerbacks. To review, the terms regular starter (a player who started at least 40 games across his first five years), impact player (a player who made a Pro Bowl in any way while also appearing in at least 40 games), and failure (a player who did not make it to at least a fourth season in the NFL) are used consistently.

Pick Cost refers to how many draft picks at a certain level it took to find a particular type of player. Likewise, Likely Players are the totals in the numbers of players found in each category divided by eight, to represent what a “typical” draft is likely to include; all totals are rounded to the nearest half player.

Edge Rusher

Overview: Just over 22 selections were made per draft on edge rushers, and based on historical trends there would be at least 5 likely starters per draft. This is the premium position on defenses, and the cost of retaining a high-level edge rusher means that teams gain a tremendous advantage for finding even a pretty good one in the draft and securing him to a price-controlled contract.

Discussion: The first thing that jumps out is that there are still 2.5 starters available per draft after day one. There’s also even a decent chance at having one impact-level player per draft after day one. That is, in fact, better than might be expected. The extraordinarily low failure rate across the first three rounds is likely indicative of the fact that even a rotational edge rusher can find work in the NFL barring unusual circumstances.

Conclusions: The profile strongly suggests that while it’s worth it to spend a pick on a highly-rated edge rusher throughout both of the first two days of the draft, the position is not isolated from the customary dropoff that happens on the third day. Meanwhile, it’s possible to delay on finding an edge rusher and still pick one up later, but the odds diminish.

Defensive Line

Overview: 27 picks in an average draft find 8 likely starters, meaning that the NFL seems to do a very good job of figuring out who can and who cannot start at this position. The profile is actually very similar to that of the interior offensive linemen, as well.

Discussion: There are starters to be found at almost every level of the draft. There were on average five left after the first day and there were even two left on the day. Note that this could be a result of necessity, in that teams need to find players to start these positions, but those are still high numbers. Less encouraging is what happens to impact players. The dropoff after the first round is massive.

Conclusions: If a team needs an impact player on the defensive line, then it needs to invest a first-round pick or get lucky. However, if the team simply needs to find a reliable starter, then this position can afford to wait.

Linebacker

Overview: There were an average of 27 picks in an average draft, locating what seems to be 7 likely starters in any given year. So far, those numbers seem pretty similar to those for the defensive line, but the actual rate of investment gets interesting.

Discussion: At one point, off-the-ball linebackers carried more importance, but as the value of getting to the quarterback has increased, the importance of these positions has suffered. It shows in terms of draft investment as well, but in a surprising way. There were 96 defensive linemen drafted in the first three rounds (producing 44 starters), but only 69 linebackers (producing 41 starters). Of particular note is the remarkably high rate of finding an impact player in the second round (2.67:1), but it’s also worth pointing out that only 2 of the 7 likely starters and only 1 of the 3 likely impact players are gone by the first round, on average.

Conclusions: Once a premier position, there seems to be no urgency in finding a good one (let alone a serviceable one). The NFL seems to think that it can wait on finding linebackers compared to other positions in the Front 7, and in general it seems to be correct.

Safety

Overview: There are barely 21 selections per draft at safety, with more than 6 likely starters to be found per draft. Given the lower level of investment with a roughly equal rate of return, NFL teams are either amazing at identifying safeties or more likely to settle for lower-quality safety play than at other positions. The numbers support the latter conclusion.

Discussion: Note that while there is only a gradual decline in the rate at which picks pay off in terms of starters found on a per-round basis, there is a dramatic dropoff in the likelihood of finding a Pro Bowl-level player. That seems to suggest that NFL teams settle for lesser players. The low failure rate as rounds go on is likely indicative of this trend as well, given that most other positions wash out of the NFL at a higher rate in later rounds (though special teams value can’t be ruled out as a factor, as well).

Conclusions: The draft outcomes of safeties reinforces the contract information on safeties signing second contracts, as well. This is a position that is drafted and filled as resources are available without urgency unless a truly special player is available.

Cornerback

Overview: With 30 selections per draft and only 6 likely starters per draft, the cornerback position is one of the ones that requires consideration of football as it is played, not spreadsheets as they are assembled. In addition to the numbers normally listed, it is worth pointing out that 16 players per draft played in at least 40 games and nearly 9 per draft played in at least 60 games. The standard definitions of starter only work so well given how often teams require three corners (and five total defensive backs) in their formations.

Discussion: Not even half of the likely starters are gone by the first round, but almost two-thirds of the impact players are taken. The profile for corners is roughly like what many people believe to be the profile for wide receivers. There might be three impact players at corner in the average draft, but two of those three are likely to be gone in the first round, and by the start of the third round, they are essentially gone. It’s also worth noting the strange little pool of corners found in Round 5. They are not all nickels, nor are they particularly consistent in how they achieved starter status or when they started to make a difference. Three were found prior to 2013 and three were found after 2014.

Conclusions: Corners present an interesting conundrum for GMs, because superficially it looks like there should be some urgency to drafting them while at the same time it seeming like it’s reasonable to wait–especially compared to positions on either line. There is a specific implication here that is related to the way defenses have changed over time that will be addressed in the third installment of this series.

Urgency and Types of Need

If impact players are equally desirable at all levels of the game, then this is urgency of drafting defensive players early–benchmarked against positions on offense that serve as key points of comparison.

The defensive line is the most urgent position under this view, with edge rushers and corners following safeties but well ahead of linebackers. Wide receivers and running backs remain the least urgent positions in the draft. In the next piece it will be time to look at stars, starters, and hidden gems.