Fantasy Football Week 17 Defense Start/Sit: Chargers, Seahawks, Vikings, Lions, Broncos

We have made it to Week 17 and the fantasy football championship round. This article will go over which defenses to trust in your lineups for the final week of the season, but first, let’s take a look back at last week’s results. Both of my Start picks from last week were huge successes, as the Bengals and Ravens both finished as top-four units with 14 or more points.

Things were slightly more mixed on the Sit side: Pittsburgh was an obvious hit with a negative outing, but Detroit (six points) and Baltimore (seven points) both provided top-12 results. Still, my Sits on average were clearly well behind my Start picks, so I will chalk last week’s results up as a win. Hopefully we can keep that momentum going and finish strong with some trophy-winning picks in Week 17. Here we go!

For more help with your toughest Start/Sit decisions, check out FantasySP’s NFL Start/Sit tool!

Fantasy Football Defenses To Start Week 17

Los Angeles Chargers @ New England Patriots

As always, I’ll start the Start section by featuring a team from my DST Streaming Picks for the week. The three other teams listed in that article (the Dolphins, Colts, and Raiders) are all still excellent picks, but the Chargers seem to be the team that most managers are debating, so here’s another quick rundown of why they are a good play.

First of all, LA’s defense is good. They rank seventh-best in EPA per play allowed and second in points per game. They give up more yards, but still rank right at average in that department. More importantly, though, New England’s offense, specifically their offensive line, is very, very bad. Sacks are the most important driver of defensive fantasy scoring, and a terrible O-line against a good defense is a surefire recipe for some sacks.

And although Drake Maye has certainly improved things, it’s not like New England’s offense is much of a threat. Their team total for this game is currently 19.5, and it opened even lower at a miserable 17.5. The Chargers should limit the damage while doing some damage of their own, making them an excellent start for this week.

Seattle Seahawks @ Chicago Bears

Seattle plays tonight in a Thursday Night Football showdown with the Bears. And this play all really comes down to one thing, which is the same reason the Bears are the seventh-softest matchup for opposing defenses on the season: Sacks. For the season, Chicago’s offense (aka Caleb Williams) leads the NFL with a massive 10.6% sack rate. There is plenty of blame to go around, as the Bears’ line isn’t great and Caleb also ranks second to only Will Levis with a massive 28.8% pressure-to-sack rate. As a result, the first-overall pick has taken exactly 4.0 sacks per game, an absurd number that provides a massive boost to the floor and ceiling of any defense facing Chicago.   

Meanwhile, Seattle’s defense has been very solid in recent weeks. Since Week 10, they have allowed the sixth-lowest EPA per play in the league. For the season, they rank eighth in the league in pressure rate, which lines up excellently with Caleb’s sack-happy ways when pressured. It can be daunting to start a defense on Thursday night, as there’s nothing worse than looking at a bad or even negative score to start your week. But Seattle’s defense is in a good spot to come through with fantasy football championships on the line.

Fantasy Football Defenses To Sit Week 17

Minnesota Vikings vs. Green Bay Packers

The number-one thing to remember when choosing a fantasy football defense is that defensive strength hardly matters. It’s all about targeting weak offenses (and quarterbacks), and the Packers are not a weak offense. They rank eighth in EPA per play, seventh in points per game, and fourth in yards per game. For the season, the Packers’ offense (mostly Jordan Love with a bit of Malik Willis) also ranks second-lowest in both sacks per game and sack rate.

Meanwhile, the Vikings’ defense has been slowing down of late. For the season, they rank second in EPA per play allowed. Since Week 10, they are just seventh, and they have given up at least 20 points in four of their last five games. They’re still a solidly above-average unit, but they don’t look elite, and that’s what they’d need to be to be worth considering against a defense as effective and mistake-free as the Packers. 

Detroit Lions @ San Francisco 49ers

In recent years, this pick would have been all about the 49ers’ elite offense. In 2024, though, they simply haven’t been the dominant force we have come to expect from Kyle Shanahan’s teams. With that said, San Francisco is still a below-average matchup in terms of points allowed to opposing defenses. They are slightly above average in most measures of offensive effectiveness, including ranking eighth in yards per game. 

However, this pick is more about the Lions’ defense. After starting the season looking like a top-tier unit to match their offense, Detroit’s defense has been ravaged by a whole host of injuries. Combine those injuries with the fact that every offense they face is going all-out to keep up with Jared Goff and Co., and you have a recipe for some rough outings. The Lions’ defense has given up over 29 points per game over the last four weeks (to be fair, they did have to face Josh Allen), finishing as a top-10 fantasy defense only once in that span. For this Monday night matchup, the 49ers have a very solid 23.5-point team total. Put it all together, and I recommend finding a different option for your championship lineup.

Denver Broncos @ Cincinnati Bengals

I honestly don’t feel the need to explain this one very much. Joe Burrow and the Bengals are on a mission to make the playoffs, and they are dropping 30 points a game to make it happen. Denver’s defense has been one of the best in the league this season, but great offense beats great defense almost every time. It worries me to see that Denver’s defense is still rostered in 75% of leagues. This is the final week of the season: If you’re not playing a defense, they should be dropped, and Denver’s defense should absolutely not be played this week. 

Ted Chmyz is a fantasy football contributor for FantasySP. Find him on Twitter @Tchmyz for more fantasy content or to ask questions.