Are Mike Davis, Peyton Barber flex-worthy in the fantasy football playoffs?

The fantasy blocking breakdown series reviews the impact that run and pass blocking have on fantasy football performance, using methodologies detailed here.

This week's fantasy blocking breakdown reviews how much trust fantasy managers should place in Mike Davis, the boom-or-bust playoff potential of Peyton Barber and making the case for Green Bay to give carries to someone other than Jamaal Williams.

How much trust can fantasy managers place in Mike Davis?

Fantasy managers stopped relying on Seattle running backs as consistent point producers many weeks ago, as before the Week 13 game against Philadelphia, the Seahawks' backs had only five double-digit point games this season, with only one of them occurring after Week 4.

That changed when Davis posted 16 carries and four receptions against the Eagles on his way to scoring 14.1 fantasy points on Sunday night. The workload is the most notable element of Davis' performance, as the 20 touches tied for the second-highest total by a Seattle running back this season.

That may be a sign that Davis finally gives the Seahawks a bell-cow ball carrier they can rely on to take pressure off of Russell Wilson, but a word of caution is in order regarding Seattle's atrocious run blocking.

The Seahawks came into Week 13 with a 37.8 percent mark this season in my good blocking rate (GBR) metric that measures how often an offense gives its ball carriers quality run blocking. That GBR total placed 28th in the league and dropped even lower after Seattle posted a 23.8 percent GBR against Philadelphia. That subpar blocking pace has become par for the course of late, as the Seahawks have now posted a GBR of less than 30 percent in five of their past eight games.

There is a strong chance that the Week 14 matchup against Jacksonville will make it six out of nine games with a GBR lower than 30 percent, as the Jaguars' defense posted a 32.4 percent GBR allowed from Weeks 7-12 and held Frank Gore to only 6.1 points in Week 13, which is his second-lowest-scoring mark of the season. The good news is the schedule does clear up after that, as Dallas and the Los Angeles Rams have both allowed a GBR of higher than 40 percent since Week 7.

This means fantasy managers probably should not trust Davis as anything more than a risky flex option next week, but ought to be able to count on him for flex or even RB2 production in the semifinal and championship weeks.

The boom-or-bust playoff potential of Peyton Barber

Barber is certainly going to be one of the most popular waiver-wire pickups this week, as his 23 carries and 18.3 fantasy points against Green Bay assure he will be rostered in far more than the 1.5 percent of ESPN leagues he was headed into Week 13.

A major factor in Barber posting those totals is the 56.7 percent GBR that Tampa Bay registered in that contest, a GBR that was the best of the season for the Buccaneers.

That bodes well for the first two weeks of the fantasy playoffs versus Detroit and Atlanta, as those defenses ranked last and 26th, respectively, in GBR allowed in Weeks 7-12 before giving up a combined total of 70 fantasy points to opponents' running backs in Week 13.

Having noted the upside, it should be pointed out there are two caveats to Barber's high point ceiling. The first and most obvious is that Tampa Bay could end up splitting the workload between Barber and Doug Martin or Jacquizz Rodgers, but that may not happen given how well Barber played against Green Bay.

The second could be of even greater concern, as before the Packers contest, the Buccaneers had posted a GBR of 33.3 percent or lower in six of their past seven games, and their composite 32.5 percent GBR during that time frame ranked 30th.

Add these up and it shows that Barber may have boom-or-bust potential in the next couple of weeks, with the arrow probably leaning fairly heavily in the direction of boom.

Making the case for Green Bay to move away from a bell-cow setup

Jamaal Williams made a strong case to take over the bulk of Green Bay's backfield rushing workload for the rest of the season, as he racked up 21 carries on his way to scoring 20.3 fantasy points against Tampa Bay.

Before celebrating this performance too much, it's worth noting that Williams' value has been based too heavily on quantity and not enough on quality. His 5.6-yard mark in my good blocking yards per attempt (GBYPA) metric that gauges production on rushing plays with good blocking is the lowest of any Green Bay running back this season and is nearly two yards lower than Aaron Jones' 7.5 GBYPA.

Jones saw only one carry against the Buccaneers, which sounds like a negative until realizing that he turned that into a 20-yard touchdown that won the game in overtime. That's the sort of performance that will almost certainly cause the Packers to consider changing their backfield to a lead/alternate workload division, with Williams being the lead back and Jones the alternate, or even making this a platoon setup with Jones and Williams getting a fairly even split in carries.

The uncertainty that the potential workload split provides could be more than offset by the fact that Green Bay's offense posted a 50.5 percent GBR in Weeks 7-12, a pace that ranked fourth highest, and kept that trend going with a 50.0 percent GBR against Tampa Bay. The Packers have also posted a GBR of 45 percent or more in eight of their past 11 contests, so quality run blocking is something Jones' and Williams' fantasy managers should be able to rely on. That trait will at least somewhat ameliorate the three tough rush defenses Green Bay faces during the fantasy playoffs (Cleveland, Carolina and Minnesota) and give Williams and Jones flex-rated potential or better in those matchups.