Which NFL rookie running backs will thrive in 2021? My analytics-based top-five rankings

According to Next Gen Stats, Steelers running backs ranked 31st in expected yards per rush last season (3.9). That's not an indictment on the RBs themselves, but rather the circumstances they faced. As of right now, the Steelers' offensive line forecasts to grade out in the 20s by the time everyone establishes their 53-man rosters, meaning Harris faces a tough task. The good news is that his volume forecasts to be high, as does his ability to keep earning positive yardage. Pro Football Focus credited Harris with earning 821 rushing yards after contact in 2020, which was the second-most in FBS (trailing only Iowa State's Breece Hall). Harris also forced 93 missed tackles on touches last season, the most in FBS, with 71 coming off rushes and 22 on receptions. My computer vision shows that his off-ball metric on short passing downs (meaning how he blocked and/or ran a route when not targeted) was the most efficient amongst all backs in the Power Five conferences last season.

The Broncos' situation is pretty much the opposite of the Steelers in terms of O-line context. Last season, Denver's offensive line helped create a scenario of 4.5 expected yards per rush (fourth-best, per NGS). But the ball carriers averaged -0.05 rush yards over expected, ranking 23rd. With Phillip Lindsay departed, Williams should have a strong chance to make an impact right away, even with Melvin Gordon still in the fold. In 2020, according to Pro Football Focus, no FBS back forced more missed tackles on rushes than Williams' 76. All in all, the Tar Heel ranked sixth in the FBS with 1,140 rushing yards, averaging a whopping 7.3 yards per carry and notching 19 ground scores. Considering he split time with another back on this list, Williams clearly made the most of his carries. The Broncos only scored 13 rushing TDs in 2020 (tied for 22nd), which means Williams has a real opportunity to establish himself as an instant red-zone threat.

Next Gen Stats reveal regression on San Francisco's offensive line this past season, at least in the ground game. The 49ers averaged 4.1 expected yards per rush last season (21st), compared to 4.6 in 2019 (third). They also dropped to 15th in rushing yards per game in 2020 (118.6) after finishing second in 2019 (144.1). The Niners did have some injuries to the unit, and the offseason addition of center Alex Mack will help. The emphasis on the run game in this offensive architecture provides enough potential volume for Sermon, but Kyle Shanahan does like utilizing a committee backfield. Sermon ended up ranking second in the Big Ten last season with 870 rushing yards (trailing only Minnesota's Mohamed Ibrahim), thanks to a prolific three-game run down the stretch that saw him pile up 636 yards and four touchdowns on the ground. Computer vision shows that Sermon's body control (measured in sustained speed when changing direction) was in the top 10 percent of backs in the past two drafts, which bodes well for his ability to be a useful weapon in Shanahan's arsenal.

Last season, the Jaguars ranked 15th in expected yards per rush (4.3), meaning their offensive line was about average on rushing downs. They took the fewest rushing attempts (337) and netted the fewest rushing TDs in the league (nine). It's still unclear how/when Etienne and James Robinson will be used, which isn't great for fantasy. But Etienne's familiarity with Clemson teammate Trevor Lawrence sure doesn't hurt his prospects, especially as a weapon in the passing game. PFF counts Etienne as forcing 187 missed tackles over the past three seasons (most in the FBS). Etienne doesn't rate higher in overall median forecasting because it's crowded in Jacksonville's backfield, not because his explosive talent doesn't warrant it.

The 2020 Jets' offensive line helped drive a 4.4 average in expected yards per rush, which ranked ninth in the NFL. Jets ball carriers, however, earned -0.39 rushing yards over expected per attempt, which ranked third-worst. Drafting guard Alijah Vera-Tucker and getting more snaps out of Mekhi Becton (who is presumably healthy) will add even more to this potentially positive O-line situation for the Jets. While they brought in veteran RB Tevin Coleman, with whom the new coaching staff is familiar, it still seems Carter has a great opportunity to perform -- and at a high level -- relatively quickly. Pro Football Focus had him averaging 4.5 yards after contact per rush last season (fifth in FBS, min. 100 rushes). Given Mike LaFleur's experience crafting play-action schemes, Carter's skills could be maximized. Carter took about 0.6 seconds longer to reach his fastest speed than the average of all running backs in this draft class, so situations where misdirection can be leveraged forecast to optimize his utility.