Small sample sizes, you've been told, can get fantasy managers into trouble. Becoming fixated on small-sample success in a game with very few large sample sizes can create fantasy football love affairs that turn sour in a hurry.
That doesn't mean fantasy players should outright dismiss all less-than-large sample sizes, especially when those opportunities -- targets and carries, to name two -- can be measured in more granular ways with data that can show us who can make the most of their opportunity, whatever the size.
Below are running backs who, for the most part, haven't been deployed as anything close to workhorses. They've popped in peripheral statistical categories though, tipping off the observant fantasy manager desperately seeking an undervalued back with upside -- someone who can make the most of his opportunity if and when it ever comes his way.
Looking at a back's yards before contact per carry can reveal which guys run to daylight, the sort of thing that leads to long gains on the ground. Yards after contact per carry shows us which backs consistently break tackles and gain more than what's blocked on a given play. Breakaway rate, as measured by Pro Football Focus, points to running backs capable of ripping off long gains and delivering the explosive runs that have long been a hallmark of hyper-efficient runners. And yards per route run can show which guys are most efficient when targeted out of the backfield.
J.K. Dobbins
It took a while for Dobbins to be deployed as anything more than a sparingly-used rotational back in 2022. When he was finally fully back from his 2021 ACL tear, Dobbins was tremendous by every measure.
Dobbins from Week 14-17 led the NFL with 397 yards on 57 rushes (7.1 yards per carry). No running back had more rushes of over ten yards (13) than Dobbins over that month-long stretch; Dobbins ranked seventh in PFF's breakaway rate on the season. Over his eight full games in 2022, Dobbins posted the league's 11th highest yards after contact per carry (3.1) and the fifth best yards before contact per carry (2.5).
Dobbins making the most of his rushing attempts is nothing new, as any Dobbins truther will tell you. In 2020, he was seventh in yards after contact per carry. A mere eight backs had a higher broken tackle rate than Dobbins that year.
Lamar Jackson's contractual fate will play an outsized factor in Dobbins' 2023 prospects, but he's proven a superb rusher even after his devastating knee injury.
James Cook
While not exactly fantasy relevant outside deep fantasy formats, Cook was quite good as a rookie. On 89 rushing attempts in a split Buffalo backfield, Cook had an elite yards before contact per carry of 3, second among all qualifying backs. He was 19th in yards after contact per carry (2.7) and led the league in PFF's breakaway rate (44.1 percent).
Cook acquitted himself well as a pass catcher too. Only nine running backs who saw at least 30 targets in 2022 had a higher yards per route run than Cook (1.7). We could see him take that role for himself with the Bills' signing of early-down banger Damien Harris, a move that should keep Cook's redraft ADP nice and suppressed throughout the spring and summer. Cook was never going to see a massive workload in the Buffalo offense. His best-case scenario -- lead back duties on a potent Buffalo offense -- and his rookie year efficiency give Cook plenty of appeal at what should be a reasonable ADP.
Rashaad Penny
Suffice it to say Penny, when healthy, is an unquestionably elite NFL back. One could go so far as to say Penny -- again, when healthy -- is the league's best running back. The numbers bear that out. The analytically-inclined Eagles, who signed Penny this week, surely know as much.
Penny during his mythical six-game run to close the 2021 regular season was sixth in yards before contact per carry (2.5) and first in yards after contact per carry (3.7). You might not be stunned to know Penny -- in four and a half games last season -- ranked ninth in yards before contact per carry and first (again) in yards after contact per carry.
Folks forget Penny was a mouth-watering prospect when he entered the NFL in 2018 who has done nothing but produce when given a halfway decent workload. Go all the way back to 2019, before a knee injury that wiped out his 2020 campaign, and see Penny led all running backs with at least 50 carries in yards before contact per rush. He had the league's second lowest stuff rate (rushes stopped at the line) in 2019.
Fantasy managers panting like dogs at the prospect of drafting Penny in 2023 can hope his long and ugly injury history suppresses his redraft ADP.
Jaylen Warren
By nearly every measure, Warren was a more effective runner and pass catcher than lumbering backfield mate Najee Harris in 2022. Warren's explosiveness -- he had a breakaway rate of 25 percent to Harris' 13 percent -- eventually forced Steelers coaches to give him more run as the season wore on. Warren saw 22 percent of the team's rushes over the second half of the season.
Warren was ninth among all running backs in yards before contact per rush and third in evasion rate, trailing only Aaron Jones and Josh Jacobs. Fourteen percent of his rushing attempts went for more than ten yards, far higher than Harris' rate of 7.2 percent.
This isn't to say that Warren is going to leapfrog Harris on the Steelers depth chart this summer. But his rookie year numbers suggest Warren should be valued as one of fantasy's top insurance backs in case Harris -- who has had a massive workload in his first two NFL seasons -- misses time in 2023.