UPDATE: This the 2021 version. The current version of this can be found here
When I started playing in IDP dynasty fantasy football leagues, I did almost no research on incoming rookie IDP players. I would get to the third or fourth round of a rookie draft where I didn’t like any of the offensive players remaining and would look at who was taken in the first round of the NFL draft, read a Rotoworld (now NBC Sports Edge) blurb written about some of the players from draft night and pick someone who sounded like a good player. That approach yielded some players that helped my team (Roquan Smith in 2018, Jamal Adams in 2016 and Keanu Neal in 2015), and others that did not (Darron Lee in 2016 and Jadaveon Clowney in 2014).
We generally know that players drafted earlier in the NFL draft are more likely to be successful professionals, and there is a lot of good work done by other on hit rate of running backs and wide receivers based on draft capital, as well as other factors like college production. I wanted to take a closer look at IDP players and how draft capital affects their success rate for fantasy.
Method
I used defensive statistics and positional data back to 2013 from Pro Football Reference. I calculated the fantasy points scored by each player and ranked them by position. Then I went though each draft year, counting a player as a success if they achieved a top 24 season at their position in their first three years in the NFL. Using the first three seasons is intended to represent the amount of time a fantasy manager will wait on a rookie they drafted before cutting them. While some players break out later in their career (Jordan Poyer in his 5th NFL season), waiting that long for a rookie pick to contribute shouldn’t necessarily be considered a successful draft pick.
Players were counted at the position they were drafted at, regardless of what position they achieved a top 24 season. For example, Foyesade Oluokun was labelled as a safety when he was drafted in the 6th round of the 2018 NFL draft, but achieved a top 24 season in 2020 as a linebacker. For the purposes of this exercise, he is counted at his drafted position of safety. Because positional data from Pro Football Reference was used, it often means that pass rushing linebackers such as Josh Allen and T.J. Watt are grouped with linebackers, even though their role on their teams in closer to the role of players drafted as a defensive end. This was done to limit the amount of subjectivity, as it isn’t always clear what the role of some players are or will be when they are drafted. One example of this is Zach Baun, who is seen by some as a pass rusher, and others as an off-ball linebacker.
IDP123 scoring was used to score players, and full description of that scoring setting can be found here. (https://www.dynastynerds.com/idp123-default-scoring-made-easy/). Different scoring settings will change the ranking of players within a position, but generally there aren’t that many differences in terms of who finished in the top 24 and who didn’t. I reviewed the effects of different scoring settings on positional finishes previously, which can be found here (https://twitter.com/djkelltown/status/1355713411330367490). This study is more a question of how many players hit instead of which players hit, so the actual scoring used doesn’t matter as much as it does in other analyses.
Results
The result are presented two ways: Once for IDP leagues that use three position designations (DL, LB and DB), and once for leagues that use five position designations (DE, DT, LB, CB and S). Every year, several defensive tackles and cornerbacks will score amongst the top 24 at DL and DB respectively, however it isn’t as frequent as defensive end or safety.
Discussion
Defensive End
The hit rate for defensive ends is around 60% in the top half of the first round, but drops off quickly to 22% in the second half of the first round. Of all the positions, it is the one with a drop off this large in the first round, although defensive tackle is close. Defensive end has some of the worst success rates after the first round.
Defensive Tackle
Defensive tackles have a big difference in success rates between 3 position and 5 position leagues. Top 16 picks have a 70% hit rate in 5 position leagues and a 30 % hit rate in 3 position leagues. This is why you often see defensive tackle premium scoring.
Over the last five seasons, there has been about 6 defensive tackles that score within the top 24 defensive linemen each season. So the hit rate in 3 position leagues is essentially the top 6 defensive tackle hit rate.
Linebackers
First round Linebackers have about a 40% hit rate in the first round, with practically no difference between the top 16 and bottom 16 picks of the round. In 5 position leagues, the other positions have higher hit rates. This is likely due to there being more spots available when the Defensive Line and Defensive Back positions getting split into two positions.
Cornerbacks
Similar to defensive tackles, cornerbacks have very poor hit rates in 3 position leagues, where they share the defensive back with safetys. The low hit rate in the top 16 picks for 3 position leagues appears to be an anomaly, as it reverts to the pattern seen in other positions in 5 position leagues. Again, similar to Defensive Tackle, about 6 Cornerbacks score inside the top 24 defensive backs in a season.
Safetys
A note of caution about the hit rate for the top 16 pick grouping; There have only been 5 safteys drafter in the top 16 picks of the NFL draft since 2013 (Kenny Vaccaro, Karl Joseph, Jamal Adams, Malik Hooker and Minkah Fitzpatrick). The next smallest group in this data set is defensive tackle (10 players).
safety features the highest hit rate in the 3rd round, about 35%. safety has the most variation in terms of the scheme used by their team, whether their team uses split safetys, dedicated deep and box safety, or how much they ask those players to pass rush. Often what NFL teams ask those players to do and what they find valuable isn’t necessarily productive for fantasy football.
Edit: April 20, 2021 – updated a typo in the description of the 3 position chart
Super Smash Pros: Fantasy Football 