In this article we assume that you are starting your RB1s, especially with the onset of the bye weeks. Each week we will analyze the match-ups and provide our take on which RBs you should start and which should be benched based on difficult match-ups, injuries, potential weather problems, conduct code violations, etc.
The most stout run defenses (allowing less than 16 fantasy PPG to opposing run games) can be found in San Francisco, Baltimore, Seattle, Denver, Dallas, Green Bay, Houston, Detroit and San Diego.
Conversely, the following defenses have been carved up by opposing ground games and rank at the bottom of the league (23-plus fantasy PPG): Carolina, Indianapolis, St Louis, Philadelphia and Oakland.
Only four teams have a Week 9 bye: Detroit, Carolina, Minnesota and Jacksonville, but fantasy owners will be left scrambling to replace Maurice Jones-Drew and Adrian Peterson. If you are in a bind be sure to check out our RB Waiver Wire Recommendations for Week 9.
Many backfields have been decimated by injuries over the past few weeks. Darren McFadden (foot), Ahmad Bradshaw (foot), Peyton Hillis (hamstring), Mark Ingram (foot) and Felix Jones (ankle) are unlikely to play in Week 9.
In Big D, Cowboys head coach Jason Garrett has hinted at a running-back-by-committe once Felix returns, so the clock is ticking for DeMarco Murray owners to get value for him in a trade (sell high!). Ahmad Bradshaw apparently has a broken foot, which could open the door for Brandon Jacobs to return to fantasy relevance against New England.
UPGRADE: Shonn Greene (at Buffalo): After the Week 4 loss to Baltimore, Rex Ryan declared that the Jets offense needed to get back to the ground-and-pound philosophy. Thanks to the change in offensive gameplan, Greene has amassed 62 carries for 269 yards and one touchdown over his past three games.
On the season, the third-year back from Iowa has been mediocre at best, averaging 61 YPG, but the increased workload makes him a solid RB2 most weeks.
In Week 9, the Jets travel to Buffalo to face a Bills defense that ranks 20th against the run (120 YPG), allowing 20 fantasy PPG to opposing run games. Greene only has two touchdowns this season, but in a favorable matchup this week he could very well approach 100 yards for the second-straight week (20 carries for 112 yards against San Diego in Week 7).
Cedric Benson (at Tennessee) returns from his one-week suspension to face the 27th-ranked Titan run defense (129 YPG).
LeGarrette Blount (at New Orleans) is expected to return from a knee injury to face the Saints 24th-ranked run defense (124 YPG).
DOWNGRADE: Rashard Mendenhall (vs. Baltimore): The stout Ravens defense is allowing the second-least fantasy points to opposing RBs (12 FPG). Baltimore ranks third in rushing yards allowed (89 YPG) and have only yielded two rushing touchdowns through seven games.
Coming off an impressive 2010 campaign (324 carries for 1,274 yards and 13 touchdowns), Mendenhall has struggled to justify his selection as an RB1 as he's averaging a pedestrian 60 YPG with three touchdowns through seven games. If you subtract his Week 6 explosion (23 carries for 146 yards against Jacksonville), his 2011 numbers look even weaker.
Over the past three seasons (six games against Baltimore), Mendenhall is averaging 20 carries for 58 YPG with five touchdowns (he's yet to top 100 yards against Ray Lewis and crew). He's a mediocre RB2 this week and don't be afraid the bench him if you have other solid alternatives.
Marshawn Lynch (at Dallas): The Cowboys have the fourth-ranked run defense (94 YPG) and have allowed the fifth-least fantasy points to opposing RBs.
Washington Backfield (Torain/Helu) vs. San Francisco: The 49ers' No. 1-ranked run defense has yet to allow a rushing touchdown.
SLEEPER: Michael Bush (vs. Denver): Bush has 60 carries for 237 yards (4.0 YPC) and is coming off a solid Week 7 performance (17 carries for 99 yards against Kansas City).
Darren McFadden's foot injury did not heal enough during the Week 8 bye week to allow him to get back on the practice field, leaving serious doubt that he'll be in uniform this Sunday. Oakland faces Denver's 17th-ranked run defense (118 YPG).
It's worth noting that the Broncos have allowed the fourth-fewest points to opposing RBs, but that is somewhat fluky based on a schedule against many weak run games (TEN, GB, DET, MIA). In Week 1, they allowed 150 yards to Darren McFadden.
Bush should produce solid RB2 numbers if McFadden is ruled out. At 6'1", 245 pounds, Bush remains a red-zone vulture (three touchdowns on the season), and this week he should produce the yardage totals to make him a borderline must start unless you have a loaded backfield.
Pierre Thomas (vs. Tampa Bay) - Mark Ingram is likely to miss another week. Tampa Bay's run defense ranks 23rd (123 YPG).
Reggie Bush (at Kansas City) - Daniel Thomas has returned to practice but is listed as questionable. Miami faces Kansas City's 22nd-ranked run defense.