Comparing current NFL draft prospects to those of years past is standard procedure in draft evaluation, though most comparisons are built on the memory recall and subjective opinion of the particular evaluator.
This will be the first in a series of articles comparing the 2021 draft prospects to prior years and picking out the most similar comps with a clearly delineated and quantifiable method.
PFF data scientist Eric Eager has done tremendous work building college-to-pro projections, which are built off the robust college data we’ve collected since 2014 and have been applied to exercises like building an “Analytics” Mock. In this analysis, I will use some of our advanced stats for comparison but primarily rely on traditional stats to go back further to compare the 2021 prospects to draft classes going back to 2006.
Without the NFL Scouting Combine this season, the important measurables like weight and 40-yard dash will be reported through the various pro days that will be taking place over the next few weeks.
The comps below were derived from a two-step process. First, I converted all the most statistically relevant stats and measurables to percentiles based on the thousands of prospects who have entered the NFL since 2006 at each position. Then, I filtered the total universe of past prospects by those who had draft positions, weight and 40 times within a 10th percentile in either direction of Kenneth Gainwell. For undrafted players, I assigned a numerical draft position of 300.
The rest of the matching features were transformed by principal component analysis (PCA). I found the closest statistically comparable players by the euclidean distance between the players' principle components, listed in the top 10 below.
The metrics for PCA are: rushing attempts per game, rushing yards per game, rushing touchdowns per game, receptions per game and market share of team receptions. All of these data points come from the prospect’s best collegiate season. I also matched the prospect’s market share of total team yards and touchdowns to past draft prospects.
For Gainwell's draft position, I’m using an estimate based on the mock data collected at GrindingTheMocks.com. For weight and 40 time, I’m using the numbers from his pro day, with a 0.03-second penalty added to the 40 time to reflect the uncertainty of pro-day timed measurements.
Most comparable players
I could only piece together measurables from Gainwell’s pro day for this analysis. The only consistent numbers I saw across social media were a weight of 201 pounds and a 40-yard dash time of 4.42 seconds. I didn’t see numbers for other drills, though the things outside of weight and speed aren’t part of the matching algorithm.
Gainwell displayed top-notch speed at the collegiate level, and he was able to erase angles against weaker competition.
— BlitzburghUSAVideos (@sdextrasmedia) March 19, 2021
The concern for Gainwell’s transition to the NFL was primarily size and whether he could hold up with a bigger workload. By weighing in at 201 pounds, Gainwell mitigated some of those concerns, but his size makes it difficult to match him with NFL workhorses.
Gainwell accumulated more than 2,000 scrimmage yards in 2019 before opting out of the 2020 season. While that sounds impressive, the combination of his relatively low rushing attempts per game match with productive college backs who transitioned into specialized roles in the NFL.
Gainwell was also part of a dynamic offense overall, which lowers his share of team yards and team touchdowns. A troubling sign for Gainwell is that he matches mostly with previous draft prospects who were taken later than his expected draft position.
The Memphis back was an extremely productive receiver, averaging 3.6 receptions per game and accounting for 18% of team receptions in 2019. At the very least, Gainwell is positioned well for a third-down role in the NFL.