Fantasy Football Fact or Fluke: These offenses have been up and down all season — which can you trust?

The search for truth — in life and of course in fantasy football — is a never-ending quest, and this year, one that has taken more than the usual twists and turns. Just when you think you know a team, a player, a matchup … the NFL will laugh in your face.

Week 10 was relatively low scoring for fantasy purposes and the points didn’t necessarily come from the expected sources. I know I’m not alone in wondering what the heck happened to Sam Darnold and Justin Jefferson against the Jaguars. Likewise, what a pleasant surprise Kyler Murray vs. the Jets turned out to be.

We support data-driven decision-making here at Yahoo Sports, but not even the most careful analysis of the most useful stats can predict every game’s outcome. We’re going to zoom out this week to look at how the first 10 weeks of the season have shaped and changed our perceptions of some of the most confounding teams in the NFL. We can’t proceed reactively, recalibrating our beliefs every time something unexpected happens. Instead, we’ll try to define a setpoint, a mean or median performance level, for a team while still recognizing that there is going to be some error around that mean.

Importantly, some of us might have to let go of our first impressions.

Week 1 memories get their hooks in us for reasons I’ve discussed before: Primacy Bias and the flood of exciting and rewarding neurotransmitters in our brains that signal the long-awaited first week of real football. Others might have gone too far in the other direction, trashing those first impressions the moment we got conflicting information.

There are a bunch of teams where our preseason expectations have been borne out, more or less. Buffalo, Detroit, Baltimore and Houston have generally been as fantasy-friendly as expected. New England, Las Vegas, Cleveland and Carolina have been about as bad as predicted, with a few bright spots for fantasy purposes (Chuba Hubbard, Brock Bowers, Cedric Tillman, Hunter Henry). Washington has been better than expected, which is always a pleasant surprise for fantasy managers who were able to select Commanders late in drafts.

Let’s take a look at where we are with some of the more volatile offenses for fantasy.

Minnesota Vikings

I was admittedly skeptical of how Sam Darnold was going to do in Minnesota this offseason. I have him in a dynasty league, but I avoided Vikings in redrafts this year. Other than the Christian McCaffrey saga, I would argue there was no greater surprise than Darnold through the first nine weeks of the season.

Then Week 10 hit. In one of the best possible matchups by various metrics, Darnold threw three interceptions and zero touchdowns. He had one other bad game, Week 5 vs. the Jets, in which he failed to score but we attributed that one to the excellent Jets’ pass defense. Only the Jaguars’ equally bad offense allowed Minnesota four field goals to earn it the win.

There are angles to the Darnold argument. One, he is finally reaching his full potential as a 2018 third overall draft pick. Two, Justin Jefferson and good coaching/game planning can hide or overcome a lot of QB flaws. Three, he had a really bad day, at least partly because this was the least in sync he and Jefferson had been all season. The three interceptions, which could have been five per Vikings reporter Tyler Forness, had more to do with bad execution and ball placement than bad decision-making.

I’m more inclined to believe that Week 10 is the anomaly and move forward assuming Minnesota will get back in its fantasy-scoring groove. It goes to Nashville for the second of a three-game road stretch in Week 11. It’s possible that the tougher matchup with a Titans’ pass defense that is allowing the fewest fantasy points to WRs and is bottom 10 to QBs will sharpen Darnold’s focus and ball placement to the point where Jefferson can bounce back, and T.J. Hockenson can have another good outing too.

I‘m not reverting to my preseason doomsday outlook just yet.

Arizona Cardinals

The Cardinals are atop the NFC West with a 6-4 record. After a high-scoring start to the season, they had a significant lull from Weeks 3-7 before bouncing back the last three games.

What is the true identity of this team?!? No one has been more frustrating than Marvin Harrison Jr. for fantasy managers.

Week 1: he’s clearly not ready for the NFL. Week 2: he’s the best steal of the draft.

There’s that whiplash, and every week since, it’s been somewhere between downright awful (five games with fewer than five half-PPR fantasy points) and just okay. It’s not really second-round production, but at least he’s healthy, right?

Given the fantasy landscape of QB and TE, both Kyler Murray and Trey McBride are every-week starters, with a disappointing performance here and there but no real cause for concern. James Conner continues to be a Zero RB poster child despite both Murray and McBride stealing some goal-line scores (McBride’s came on a fumble recovery — he still hasn’t caught a receiving TD this season).

The Cardinals are on bye in Week 11, but then get a pretty soft schedule: Seattle twice, Minnesota, New England, Carolina, L.A. Rams, San Francisco. The whole reason we came up with the premise of a mean, an average, is that nature produces a lot of variation. No team, no player, is perfectly consistent, but I believe in the Cardinals’ ability to keep their four top players fantasy-relevant and would go so far as to wager that we’ve already seen the worst of Harrison Jr. for this season.

Kansas City Chiefs

I’ll be brief here, but these 9-0 Chiefs aren’t the kind of good team we were talking about when we drafted KC players in September. Patrick Mahomes is climbing his way back into fantasy relevance as QB14 (QB3 in Week 9 and QB11 in Week 10). Travis Kelce is somehow TE5, averaging just 10 fantasy points per game (on nine targets, 55 yards per game with just two touchdowns). Kareem Hunt is RB29, by far the best fantasy asset on this team right now. Xavier Worthy is averaging 4.8 targets and 27 receiving yards per game. Those numbers make him startable in leagues requiring five starting WR slots (too bad I don’t know of any). DeAndre Hopkins just joined the team and paired a great game (8-86-2 in Week 9) with a weak one (4-56 in Week 10).

KC plays the game of the year in Buffalo next weekend, then gets Carolina and Las Vegas, two of the most fantasy-friendly matchups, in Weeks 12-13. Start Hunt, start Kelce, but look elsewhere for your QB/WR production next week.

This is your classic case of a good NFL team not being great for fantasy. It takes some of the fun out of an undefeated season, for sure, but if you haven’t pivoted from your Chiefs receivers yet, now’s the time.

Indianapolis Colts

I remember writing excitedly about new head coach Shane Steichen this offseason and thinking of how the Colts were primed to become the new Ravens or Bills. Those dreams have come to a screeching halt. Anthony Richardson is getting robbed of his right to develop right now and Joe Flacco is not the answer for the 4-6 Colts.

Fantasy-wise, they’ve both been bad (~12 fantasy points per game), and real-life-wise, they’ve both been bad. Jonathan Taylor is the only reliable fantasy starter from the Colts. Despite seeing hints of relevance from Alec Pierce and Josh Downs, it’s impossible to trust either of them on a weekly basis.

We were wrong about Indy, really wrong. It’s ok to admit it and move on.

Tennessee Titans

This is somewhat more of a blurb for SuperFlex and Best Ball managers, who were uniformly high on the possibility of a Will Levis second-year breakout. This did not pan out.

Or did it?

Is Week 10 too late to make a comeback, Will? Against the Chargers, the NFL’s most stingy defense, Levis racked up 175 passing yards, 41 rushing yards and two passing touchdowns. It wasn’t high volume, but it was efficient as Levis completed 78% of his passes with no interceptions. Calvin Ridley (5/84/2) accounted for both TDs, but one was near the end of the fourth quarter with the game out of reach.

Beyond the fantasy points, it’s worth noting that Levis was also sacked seven times in the loss, bringing the Titans’ average to 3.1 sacks allowed per game (T-sixth most). Sadly, I think the arrows are pointing more down than up for Levis, Ridley and the Titans. Minnesota makes for a tough Week 11 matchup for running backs and quarterbacks, though it is allowing more fantasy points to receivers than average. I suspect the pressure from the Vikings’ pass rush will be too much for Levis, and I think we’ll see him revert to a less efficient, more mistake-prone game. Start only Ridley this week.

New Orleans Saints

The Saints toyed with our emotions the first two weeks of the season. A wildly successful 47-point season opener followed by a 44-point victory over a Cowboys team we all believed was going to be a juggernaut on both sides of the ball had us all eating po’boys and wearing Mardi Gras beads.

Weeks 3 and 4 brought us back down to PB&Js pretty quickly as Derek Carr went from a 6:1 TD:INT ratio to a 1:2 ratio. The biggest hurt was that it was Rashid Shaheed, not Chris Olave, who was the star receiver those first two weeks. Carr returned from an oblique injury in Week 9 to lose to Carolina (blame the NO defense for that), but is coming off his best game of the year after beating Atlanta in Week 10 (269/2 with no picks or sacks taken).

Alvin Kamara is the no-brainer must-start cog in this offense, but what about the receiver room? With Shaheed done for the year and Olave on IR until at least Week 15, it was Marquez Valdes-Scantling who came out of nowhere to catch three passes for 109 yards and two scores. It’s worth noting that he’s done this to fantasy managers before, and the three targets are concerning. I chase volume, not big plays. MVS is fast and has great sideline awareness, but he’s never been able to fill a Davante Adams, Tyreek Hill, Stefon Diggs-like role, which is why he’s moved from team to team over his seven-year career.

Don’t overbid on him thinking 20 fpts/game is what you’re getting going forward. The Saints have a nice upcoming schedule outside of a Week 12 bye: Cleveland, L.A. Rams, NY Giants, Washington, but then they get Green Bay and Denver in the fantasy playoffs. If your roster is decimated and you need a Week 11 win and can get MVS cheap (that’s a lot of ands), go for it. Otherwise, Kamara is the only fantasy player I trust from this offense.