We spend a lot of time projecting players’ most likely outcomes. Considerably less energy is devoted to forecasting the extreme ends of the spectrum. What will happen if everything goes right? If it all goes wrong? This is not a mathematical endeavor, but a reasoned attempt at guessing players’ poles. Body of work, age, injury history and supporting cast are all taken into account. Although health is considered, it is also assumed that the true “worst-case scenario” for any NFL player is “ruptured Achilles’ as he falls from cart following torn ACL.” The quarterbacks list can be found here.   

Note: Rankings are based on Evan Silva’s “July Top 150.” For complete rankings and projections, be sure to order the Rotoworld Draft Guide.

1. David Johnson

Best Case: The 21st century’s Marshall Faulk, Johnson breaks Chris Johnson’s 2009 yards from scrimmage record of 2,509. For good measure, he breaks Matt Forte’s 2014 running back receptions record of 102.

Worst Case: Ridden into the ground last season, Johnson’s yards per carry dips from 4.22 to sub-4.00. His yards per catch falls below 10.0. Defenses tee off on a tired back as Carson Palmer presents zero downfield threat in the passing game.

2. Le’Veon Bell

Best Case: Appearing in all 16 games for just the second time in five NFL seasons, Bell matches last year’s average of 157 yards from scrimmage, making him, not Johnson, the man to break Chris Johnson’s record (by three yards).  

Worst Case: Playing under the franchise tag, Bell suffers a couple of minor injuries instead of one big one, staggering his appearances, killing his conditioning and sapping his numbers. Even at age 25, Bell looks like a back who’s run a ton of miles, leaving the Steelers with a tough decision to make in free agency.

3. Ezekiel Elliott

Best Case: Elliott betters his rookie rushing total of 1,631 even as he serves a one-game suspension. His yards per carry holds steady at 5.1, and his touchdown total spikes from 16 to 18.

Worst Case: Surprisingly suspended for four games, Elliott looks rusty instead of fresh upon his return. Playing a brutal schedule, the Cowboys also miss RT Doug Free and RG Ronald Leary more than expected. Conditions ripe for a sophomore slump produce as much.   

4. LeSean McCoy

Best Case: New coach Sean McDermott’s minor refinements to the Bills’ bully rushing attack not only work, they get Shady above 1,300 yards rushing for the first time since 2014. No longer vultured by Mike Gillislee, McCoy finds the end zone 15 times as a runner.  

Worst Case: McDermott changes the rushing scheme more than expected, interrupting Shady’s flow behind an offensive line that takes a step back on its dominant 2016. Combined with his typical soft-tissue woes, McCoy has an age-29 campaign that looks every bit its number.   

5. Melvin Gordon

Best Case: Unleashed by run game maestro Anthony Lynn, Gordon maintains last year’s volume while dramatically improving his efficiency. He finishes in the top three in rushing and top five in yards from scrimmage.  

Worst Case: Coming back from another knee injury, Gordon’s YPC remains in familiar territory: < 4.00. The third-year back doesn’t come close to appearing in all 16 games, putting talk of untapped potential to rest.

6. DeMarco Murray

Best Case: Murray more or less duplicates his 2016, only this time reaching 10 scores on the ground. He ensures he’s retained at his scheduled $6.25 million price tag for 2018.  

Worst Case: On the doorstep of 30, Murray’s lost step is particularly costly, as Marcus Mariota and Derrick Henry both come into their own. By mid-October, Murray is a clear No. 3 behind the passing game and Henry.

7. Jay Ajayi

Best Case: The focal point of offensive mastermind Adam Gase’s attack, Ajayi averages over five yards per carry and leads the league in rushing. One of his four 200-yard games comes in the postseason.

Worst Case: The Dolphins’ offensive line can’t get healthy, making consistency and game flow hard to come by. Desperate to make something happen, Gase gives a surprising amount of touches to change-of-pace back Kenyan Drake, rendering Ajayi a touchdown-dependent RB2.

8. Devonta Freeman

Best Case: I’m the captain now. Emphasized by new OC Steve Sarkisian, Freeman’s touches increase by 50 to 331, and he’s no longer victimized by Tevin Coleman’s fluke touchdown rate. Freeman is a top-five RB1 for the second time in three years.

Worst Case: A torrent of Coleman home runs in September narrows Freeman’s touch advantage. Unable to get into rhythm, Freeman struggles to keep his YPC above 4.00 while failing to reach 10 touchdowns.

9. Jordan Howard

Best Case: Howard leads the league in rushes, touches and rushing yards, only narrowly missing No. 1 overall status. The overall game he displayed as a rookie — chain moving, big plays and pass catching — is here to stay.

Worst Case: Howard cuts to the Alfred Morris chase, making it appear his rookie campaign will be his career year. Awful quarterback play, a league-average line and too many cooks in the third down kitchen all play a part in Howard’s regression.   

10. Todd Gurley

Best Case: With the weight of Jeff Fisher’s world off his shoulders, Gurley is a new man in Sean McVay’s offense, getting his YPC back above 4.50. The 2015 Offensive Rookie of the Year glides by 1,500 yards from scrimmage as McVay gives him a surprisingly big role in the passing game.  

Worst Case: Fisher is gone, but the brick walls of the Rams’ offensive line are not. A strict two-down back as McVay insists on featuring Lance Dunbar in passing situations, Gurley occupies the unwanted middle ground between Trent Richardson and Alfred Morris.

11. Leonard Fournette

Best Case: Fournette can’t quite match Jordan Howard’s rookie season, but immediately serves his purpose, averaging 4.50 yards per carry while surpassing 1,200 yards rushing and 10 touchdowns. Most importantly of all, he does his part in hiding Blake Bortles.

Worst Case: Playing closer to his Combine weight of 240 than Jags-listed 228, Fournette looks bulky and struggles early, allowing Chris Ivory back into the early-down mix. That coupled with continued game-flow/Blake Bortles issues keeps Fournette below 800 yards and out of RB2 territory.  

12. Lamar Miller

Best Case: With Deshaun Watson actually threatening opposing defenses, stacked boxes aren’t the norm for Miller. His yards per carry returns to the 4.5-5.0 range he typically averaged in Miami, making for a textbook post-hype awakening Year 2 in Houston.

Worst Case: The Texans’ passing game is somehow worse than last season, putting Mariana Trench-levels of pressure on the backfield. Miller once again wilts, battling various minor injuries while struggling for the big plays he made his name with in Miami. There’s a committee by year’s end.

13. Joe Mixon

Best Case: With Giovani Bernard’s (knee) rehab dragging on, Mixon seizes immediate control of all three downs. He never looks back, blowing by 1,600 yards from scrimmage while scoring 15 total touchdowns.  

Worst Case: Bernard is healthy enough for third downs and Jeremy Hill — surprisingly kept around — is ready to vulture at the goal line. Mixon is a gross summer overdraft who capsizes fantasy teams.

14. Isaiah Crowell

Best Case: The centerpiece of the Browns’ offense, Crowell is a top-five rusher behind a much-improved line. Averaging over 5.0 yards per carry, Crowell resembles LeSean McCoy in Buffalo.  

Worst Case: Cleveland’s hard-to-believe game-flow issues carry over from 2016, severely limiting Crowell’s opportunity. Desperate to make anything happen on offense, coach Hue Jackson gives Duke Johnson his long-overdue look on early downs. Crowell turns in fewer than 800 yards from scrimmage.

15. Ty Montgomery

Best Case: Montgomery’s freakish tackle-breaking ability survives the transition to bigger workloads, making him a stunning contender for the league’s rushing crown. Along the way, he keeps catching passes, putting him amongst the league leaders in yards from scrimmage.

Worst Case: The Packers keep Montgomery in the 8-12 touch range after he continues to struggle with nicks and bruises in September. The carousel starts spinning with fourth-rounder Jamaal Williams and fifth-rounder Aaron Jones.

16. Carlos Hyde

Best Case: Healthy and focused, Hyde wins over skeptical new coach Kyle Shanahan in camp, rendering fourth-rounder Joe Williams an afterthought as Shanny’s new Tevin Coleman. Hyde not only posts his first 1,000-yard season, he coasts by 1,200.

Worst Case: Williams steals starting duties in the preseason, leaving Hyde for breather scraps and a once-a-month vulturing. That is, when Hyde manages to stay on the field and off the trainer’s table. He’s allowed to walk in free agency.

17. Christian McCaffrey

Best Case: Talent takes over. McCaffrey refuses to remain quarantined to the passing game, pushing for 20 weekly touches. He averages five yards per carry, 10 yards per catch and cruises to Offensive Rookie of the Year honors.

Worst Case: The Panthers employ McCaffrey like Danny Woodhead. This is a problem since Cam Newton remains astonishingly ineffective in the short-passing game. McCaffrey’s talent is wasted, leaving fantasy owners with a complete dud of a pick.

18. Marshawn Lynch

Best Case: Checks are cashed behind the Raiders’ elite offensive line, as Beast Mode leads the league in rushing touchdowns. Fans barely notice his 4.2 yards per carry.  

Worst Case: Lynch, a 31-year-old back who spent 2016 traveling the world and averaged 3.75 yards per carry in his most recent NFL season, looks it. He’s a vanity purchase, one sour about falling behind Jalen Richard and DeAndre Washington on the depth chart. Re-retirement is on the table from Week 5 forward.

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19. Mark Ingram

Best Case: Ignoring the Hall-of-Famer in his rear-view mirror, Ingram refuses to let Sean Payton play games, bullying his way to another 5.0/1,000 season as a rusher. His 12 total touchdowns are the most of his career.

Worst Case: Peterson makes like Beric Dondarrion, coming back to life for the third time. Payton is infatuated, Ingram is infuriated. He struggles for five touchdowns as his carries and catches both plummet.

20. Dalvin Cook

Best Case: Easily dispatching Latavius Murray, Cook blows by 300 touches. He does so as the beast he was on college film, not the back who disappointed at the Combine. The Vikes have a poor man’s Jamaal Charles on their hands.

Worst Case: Running behind one of the league’s worst offensive lines, Cook plays down to his measurables. He lets Murray take the lead on early downs and even loses passing-game work to Jerick McKinnon. He’s a second-round Laquon Treadwell.

21. Tevin Coleman

Best Case: Coleman’s absurd touchdown rate declines, but he somehow becomes even more efficient. His yards per catch falls from 13.6 to 12.0, but he gets his yards per carry above 5.0. Dynasty league owners start fantasizing about where Coleman will sign in 2019.    

Worst Case: Dealing with a newly-paid Devonta Freeman, new OC Steve Sarkisian reorganizes the backfield, making Freeman a true bell-cow. Coleman tallies a career-low 75 carries, and his catches fall from 31 to 20. He scores three total touchdowns.  

22. Adrian Peterson

Best Case: Playing for the best offensive coach of his career, Peterson once again woodsheds age, as well as Mark Ingram. He rushes for 10 touchdowns for the ninth time in nine proper seasons as his YPA fluctuates between 4.5 and 5.0.

Worst Case: Peterson makes for a nice mantelpiece on the sideline, at least when he isn’t stewing about Ingram remaining the Saints’ feature back. “adrian peterson saints” is a fun Google Images search in 2027.  

23. Danny Woodhead

Best Case: Woodhead duplicates his San Diego career years, catching 75 passes while vulturing five touchdowns as a rusher. The annual PPR lifehack is even an RB2 in standard leagues while Kenneth Dixon is suspended.

Worst Case: Coming off a torn ACL, Woodhead looks every bit his 32 years. The telepathic connection he displayed with Philip Rivers is lethargic with Joe Flacco. Dixon sees plenty of third-down work upon his Week 5 return. Woodhead is waiver wire fodder even in PPR leagues.

24. Mike Gillislee

Best Case: Gillislee can’t match LeGarrette Blount’s 18 touchdowns, but his 1,200 yards rushing are the most by a Patriots back since 2012. He’s a no-frills RB2 with little difference between floor and ceiling.  

Worst Case: Bill Belichick does more mixing and matching than anticipated on early downs, making Gillislee wildly difficult to forecast on a weekly basis. He settles in as an RB3 with a zero-point floor.

25. Bilal Powell

Best Case: Powell quickly leaves a decrepit Matt Forte in the dust, making the Jets’ “committee” a one-man show. With so little surrounding talent, Powell can’t match last year’s gaudy yards per carry (5.51), but his three-down role and touchdown opportunity make him a mid-range RB2 who mixes in RB1 weeks.   

Worst Case: The wheels are merely the first thing to fall off for Gang Green as things go so far off the rails no Jet is a safe start in fantasy. Powell and Forte are joined by a host of other committee members, ultimately rendering Powell a desperation FLEX option.   

26. Eddie Lacy

Best Case: Lacy and the Seahawks’ running game are a chicken/egg of revival, with it being unclear who deserves more credit for sparking the other. Lacy appears in all 16 games, finishing as both a top-eight rusher and standard leaguer.  

Worst Case: Demoralized behind an offensive line that’s somehow even worse than it was in 2016, Lacy sheds carries instead of pounds. Thomas Rawls is the healthier, fitter runner, and better option behind a blocking group that forces ball carriers to create their own yards.  

27. Spencer Ware

Best Case: Ware doesn’t have to hold off Kareem Hunt in training camp because he’s so obviously ahead of him from Day 1. Ware matches his robust two-year averages in yards per carry (4.63) and catch (11.6) and holds up better down the stretch than he did in 2016. He improves upon last year’s RB14 finish in PPR.  

Worst Case: Coach Andy Reid’s hand-picked back, Hunt wins a rigged camp “competition” before quickly establishing himself in the regular season. Ware is reduced to change-of-pace/breather status, becoming tough to hold onto in fantasy leagues once bye week season begins.

28. Doug Martin

Best Case: With the Bucs committed to a balanced attack, Martin is an RB1 from his Week 4 return onward. Even on an abbreviated schedule, he scores 10 touchdowns for the Bucs’ on-the-rise offense.   

Worst Case: Although his life back on track, Martin’s running remains sluggish, leaving an opening for teacher’s pet Jacquizz Rodgers and rookie Jeremy McNichols. Charles Sims keeps his roster spot. Martin is essentially 2015-16 Jeremy Hill.  

29. Theo Riddick

Best Case: Back to full health, Riddick bests David Johnson for the running back receptions crown. Riddick also has his first 100-carry season as the Lions mix and match on early downs.  

Worst Case: Ameer Abdullah breaks out to the point that the Lions no longer employ Riddick as a Woodhead-ian pass catcher. He becomes Shane Vereen on the Giants 2.0, limiting even his PPR appeal.  

30. Frank Gore

Best Case: The Colts’ offensive line finally takes a step forward, getting Gore above 4.0 yards per carry for the first time in Indy. His eight rushing touchdowns are his most since 2013.

Worst Case: Gore’s tank goes bone dry, forcing the Colts to work Robert Turbin and Marlon Mack into heavy rotation. Gore’s retirement decision is made for him.

31. Derrick Henry

Best Case: Henry is too good to ignore. Already impressing in September change-up duties, Henry gets a feature chance when DeMarco Murray goes down with injury. He never looks back, leading the run-heavy Titans’ backfield and establishing himself as the long-term starter.

Worst Case: Murray’s 2016 renaissance continues, as Henry’s veteran teammate stays healthy and productive after learning hard lessons early in his career. Henry’s 2016 touch total (123) actually decreases as Murray gallops to top-five status.  

32. Paul Perkins

Best Case: Perkins performs so well on early downs he begins eating into Shane Vereen’s snaps in passing situations. He rides big plays and goal-line work to top-18 status at running back.  

Worst Case: Underwhelming in camp, Perkins not only fails to challenge Vereen in the passing game, he lets rookie Wayne Gallman into the picture on early downs. The Giants’ backfield remains a muddled mess that’s all but useless from a fantasy perspective.

33. Ameer Abdullah

Best Case: Abdullah lives up to his draft reputation as a SPARQ stud home run hitter, making so many plays in the running game he cuts into Theo Riddick’s passing-game usage. The third-year pro flirts with RB1 status.

Worst Case: With third downs out of the question, Abdullah has to make the most of his chain-moving opportunities. He doesn’t, letting Zach Zenner and Dwayne Washington cut into his workload while Matt Asiata is subbed in near the goal line. The Abdullah dream is dead after three years.

34. C.J. Anderson

Best Case: Anderson finally manages to stay healthy, leading to increased reliability for the Broncos and consistency for fantasy owners. There are still dud games behind Denver’s shaky offensive line, but Anderson finishes as a mid-range RB2.

Worst Case: Anderson picks up an early injury in camp while Jamaal Charles looks surprisingly healthy. The rest is history as Anderson struggles to stay off the injury report and Charles wins Comeback Player of the Year honors.

35. LeGarrette Blount

Best Case: Blount’s touchdown total decreases by 10, but he posts his second straight 1,000-yard season after going five years without a 1K campaign. The yards come easy behind Philly’s excellent line.  

Worst Case: Even with plus run blocking, Blount finds that no Tom Brady equals more brick walls to run into. Philly’s crowded backfield sprawls into an unwieldy committee as Blount fails to surpass 600 yards.

36. Kareem Hunt

Best Case: Coach Andy Reid is in love from Day 1, giving Hunt extensive work on all three downs. Hunt finishes as a top-three rookie back in one of the deeper classes in recent memory.  

Worst Case: Spencer Ware mounts a surprisingly robust defense of feature status, while quarterback woes and a brutal schedule make for persistent game-flow issues. Hunt can’t get on the RB3/4 map as a first-year NFLer.

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