What to Expect from Bears RB Roschon Johnson

The first step is to find comparable players to Johnson. In order to do this, I weighed NFL Draft measurements, rushing, receiving, and blocking stats for each player's final year of college (per PFF), as well as game experience. 

Size and Athleticism

These two factors combine to account for 50 percent of the final similarity score. For the "Size" portion, I used height, weight, arm length, and hand size. Hand size has a much lighter weight than the other factors, for obvious reasons.

For the athleticism portion, I used the athletic tests that Johnson completed between the combine and his pro day. This includes the vertical jump, broad jump, 40-yard dash, and 10-yard split. I excluded bench press, because including it tends to cut the player pool down significantly.

Rushing Stats

The "Rush" factor includes PFF rushing grade, usage rate, yards per attempt, missed tackles forced per attempt, explosive run rates, and 1st down rates for their final year of college. This factor is weighted at 30 percent of the final similarity score.

Usage

The "Usage" factor accounts for how often a running back was asked to run a route, saw a target, was asked to pass block, and how they faired in completing those tasks. This factor is weighted at only 10 percent of the final similarity score.

Experience

This factor is here to make more subtle differentiations between the data. It is only weighted at 5 percent of the final similarity grade. This includes the player's age, number of games played at the college level, and the percentage of snaps played in their final year of college.

Projecting Roschon Johnson's Rookie Season

Based on the 10 most comparable players, I would expect to see Johnson hang around somewhere between starter and running back by committee. That likely means somewhere between 20% and 40% of total offensive snaps. Given his size, pass blocking acumen, and willingness to run through contact, there is a lot of reason to think that Johnson might take on a larger role. But I would be surprised by anything more than 50% of the snap share, personally. 

While Johnson has some very intriguing traits, one thing he does not have like the other running backs on the Bears roster is breakaway speed. 

What you might notice in the table above is that Johnson has by far the slowest 40-yard dash amongst Bears running backs. However, he does have the fastest 10-yard split. That is a little bit odd, isn't it? I think the best way to explain this is with the old saying "doesn't have a 5th gear". He can get up to his top speed within 10 yards, but he doesn't have much juice beyond that. So, while I do expect Roschon to take a pretty decent bite out of the running back snaps, I think we see Herbert and Foreman get decent shares as well due to their explosive abilities.