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.
Week 9 Results
Kansas City (vs Jacksonville) - 2 sacks, 3 fumble recoveries, 1 INT
The Chiefs were able to convert some key plays against the Jaguars, including recovering a Chris Ivory fumble at the goal line. Justin Houston is going to be activated this week, so the Chiefs D/ST will get even better. A solid hit for a rent-a-defense.
A Look Ahead: @CAR LA @DEN - The Chiefs are on the road, but Cam Newton has been shaky at times lately. It might be worth it to stick with the Chiefs so you can play them against the Rams in Week 11.
Baltimore (vs Pittsburgh) - 2 sacks, 1 INT, 1 ST TD
The punt block touchdown made the Ravens a hit this week, but the low sack/takeaway numbers hide a dominant defensive performance for most of the game. They were able to take advantage of a rusty Ben Roethlisberger coming back off of knee surgery, perhaps a week or two early.
A Look Ahead: CLE @DAL CIN - The Ravens are probably the top rent-a-defense this week.
San Diego (vs Tennessee) - 2 INT, 1 fumble recovery, 2 DEF TD
The biggest D/ST play of the week, San Diego was able to notch two defensive scores against Marcus Mariota in the highest scoring game of the week.
A Look Ahead: MIA BYE @HOU - Jay Ajayi has made the Dolphins a less attractive D/ST matchup target, but the Chargers D/ST has been a top five D/ST in many scoring systems this year, so they are worth staying with through their bye.
Green Bay (vs Indianapolis) - 2 sacks, 2 INT
The Packers suffered a stunning loss to the Colts, but their defense was still able to force a few turnovers and put up an acceptable D/ST score for a rent-a-defense.
A Look Ahead: @TEN @WAS @PHI - The Packers will be on the road, but Marcus Mariota paid off last week with two turnovers that turned into touchdowns
Miami (vs New York Jets) - 3 sacks, 2 INT, 1 ST TD
Kenyan Drake’s kickoff return score won the game for the Dolphins, and it might have won some fantasy matchups this week. The Dolphins were also able to take advantage of Ryan Fitzpatrick to make them the #2 D/ST this week in most scoring systems.
A Look Ahead: @SD @LA SF - The Dolphins should be thrown back as they go on the road to face Philip Rivers
Coulda, Shoulda, Woulda
Indianapolis (at Green Bay) - 3 sacks, 1 INT, 1 ST TD
The Colts were able to frustrate Aaron Rodgers for three quarters, and Jordan Todman’s kickoff return keyed a big upset win on the road.
Week 10 Candidates
Arizona (vs San Francisco)
The Cardinals are probably owned in most leagues, but coming off of two duds and a bye, perhaps they got dropped in a bye week crunch. The 49ers offense is vulnerable to meltdowns, especially on the road and the Cardinals defense has the personnel to capitalize.
A Look Ahead: @MIN @ATL WAS - If the Cardinals perform as expected in this one, they could be a consideration, even on the road, because of the state of the Vikings offense.
Baltimore (vs Cleveland) **Thursday**
The Thursday night game should add some potential for lack of preparation, the Ravens are at home, their defense is red hot after shutting down the Steelers, and Cody Kessler is starting for the Browns.
A Look Ahead: @DAL CIN MIA - We’ll toss the Ravens back this week, but may revisit them as a choice when they come home in Week 11.
Carolina (vs Kansas City)
The Panthers defense is hot right now even though their offense is not. They are coming home where they have had outstanding D/ST performances against Arizona and San Francisco this year. The Chiefs are a conservative offense so this could be a defensive stalemate, but if the Panthers can build a lead, they could swarm Alex Smith.
A Look Ahead: NO @OAK @SEA - If the Panthers convert this home matchup, they could be on the edge of consideration despite the matchup with Drew Brees next week.
Los Angeles (at New York Jets)
The Rams are on the road, so it seems unconventional to play them. The Jets might be the intuitive choice because they are home and facing Case Keenum, but they have been an anemic D/ST. The Rams D/ST’s two biggest weeks this year have been on the road, and they came out of the bye strong last week, led by Aaron Donald’s superhuman performance.
A Look Ahead: MIA @NO @NE - If Miami struggles at San Diego this week and the Rams frustrate the Jets, we’ll come back to them.
San Diego (vs Miami)
The Chargers are actually a top five D/ST in many scoring systems, so they might not be available as a rent-a-defense. If they are, they can continue their surprising season as long as Philip Rivers can build a lead and then force the Dolphins out of their Jay Ajayi comfort zone.
A Look Ahead: BYE @HOU TB - It’s hard to justify carrying a second D/ST through a bye, but if the Chargers keep up their hot streak, they could be worth it with Brock Osweiler on the other side of the week off.
Washington (vs Minnesota)
Minnesota’s offensive line is crumbling, and even though their offense is conservative, Washington’s defense has at least three sacks in the last four games, and they have playmakers like Josh Norman and Ryan Kerrigan to pounce if Sam Bradford has to play from behind on the road. Many of my rent-a-defense’s this week are possibly owned, but coming out of the bye, Washington should be available.
A Look Ahead: GB @DAL @ARI - If they can win comfortably and post a good D/ST line, Washington will be a consideration even against Aaron Rodgers with the home field advantage.
Week 11 Preemptive Pickups
If you like to devote two roster spots to a D/ST, or you suspect other teams are going to stream defenses this year, you might want to grab a top option for next week to stash away. Here are the best ones to target:
Kansas City (vs Tampa Bay)
Oakland (vs Houston)
Pittsburgh (at Cleveland)
New England (at San Francisco)