Unless most of the teams in your league carry a backup defense, more than half of the league should be available to you every week. Perhaps instead of playing one above average defense every week, regardless of matchup, we should instead target the widely available waiver wire defenses with the best matchups in any particular week? You can always make exceptions if your rent-a-defense gets hot - heck, you might find a team worth starting all year by accident. Even if you don't, good matchups will continue to get greater in number as more QBs get injured or yanked as the season goes on. You can steal some points from bad weather come December. Each week I'll list the startable fantasy defenses on most waiver wires and rank them.
**Houston has a great matchup this week but is assumed to have been drafted in all leagues**
Week 1 Candidates
Pittsburgh (at Cleveland)
The Steelers have an ADP around D/ST10, so they might not be there, but if they are, pounce. DeShone Kizer could be a very good NFL quarterback in time, but first debut could be ugly against the blitz-happy Steelers. Perhaps Kizer’s mental toughness, mobility, and arm talent will make this more interesting than it looks on paper, but if the Steelers high-octane offense can stake the defense to a lead and force Kizer to take more risks, it should result in some big plays for Pittsburgh’s defense.
A Look Ahead: MIN @CHI @BAL - If Steelers come out of the gate hot and the Vikings offensive line struggles spill over from the 2016 season and 2017 preseason, the Steelers will be a good play in Week 2 and probably beyond.
Carolina (at San Francisco)
The Panthers have an ADP around D/ST10, so they might not be there, but if they are, you get a chance to start an aggressive defense against Brian Hoyer, which is always a treat. There’s a chance Kyle Shanahan’s playbook keeps the Panthers top notch linebackers and defensive tackles off-balance, but the 49ers defense is in flux and the Panthers will have some surprises of their own with Christian McCaffrey in tow (assuming Cam Newton’s first regular season game after shoulder surgery is uneventful). Hoyer is subject to implosion at any time, although it would be more ideal if this was a road game.
A Look Ahead: BUF NO @NE - Part of the draw of drafting/picking up the Panthers for this week is having them for the home opener against the ghost of the Bills next week.
Los Angeles Rams (vs Indianapolis)
We wish Aaron Donald’s holdout was over so he could be part of the feeding frenzy, but the Rams are getting to play against a quarterback that the Colts did not intend to start Week 1. They even traded for Jacoby Brissett on the eve of the season to push Tolzien for however long Andrew Luck is out. The Rams defense has some problems up front without Donald and Dominique Easley, but they still have a great set of linebackers and Trumaine Johnson against a Colts offense that is overmatched against any NFL defense without Luck. The Colts have also looked discombobulated and morose in the preseason and the Rams have some spring in their step under new head coach Sean McVay.
A Look Ahead: WAS @SF @DAL - Unless Donald is uniform and Washington craters against the Eagles in Week 1 (possible), we will move on from the Rams.
Buffalo (vs New York Jets)
The Bills defense didn’t suffer the same kind of losses that the offense did this preseason, although they are still adjusting to a new scheme under head coach Sean McDermott. The front four is strong while the secondary features four new starters. They won’t need to be in top form to fluster Josh McCown, who is playing behind a piecemeal offensive line with a ragtag group of receivers. The Bills playing at home is another crucial factor pushing us to count on their defense in this opener between two of the NFL’s five worst teams.
A Look Ahead: @CAR DEN @ATL - The Bills don’t play the Jets again until November.
Cincinnati (vs Baltimore)
Even without suspended linebacker Vontaze Burfict, the Bengals defense still sports Carlos Dunlap and Geno Atkins up front, which might be enough to consistently disrupt a Ravens offense that is limping into this game with an offense that hasn’t had its key pieces practice together all summer. Joe Flacco has been out with a back problem, so he hasn’t played a snap with Jeremy Maclin or Danny Woodhead (who is coming in with a hamstring problem of his own). The Ravens don’t want to be opening on the road playing inside of the division in this state and you can take advantage of it.
Atlanta (at Chicago)
Mike Glennon was shaky through the first two weeks of the preseason, so it’s reasonable to expect a good chance that he struggles in his first regular season game as a Bear, especially against a retooled Falcons defense that still features Vic Beasley Jr and almost Super Bowl MVP Grady Jarrett. Bears offensive line lynchpin Kyle Long may not play, and the team just lost their best wide receiver. The Falcons should be able to move the ball on the Bears poor secondary and put Glennon on the spot.
A Look Ahead: GB @DET BUF - We’ll come back to the Falcons in Week 4.
Week 2 Preemptive Pickups
Oakland (vs New York Jets)
Carolina (vs Buffalo)
Tampa Bay (vs Chicago)
Pittsburgh (vs Minnesota)
Baltimore (vs Cleveland)