Week 15 marks the start of fantasy football playoffs for most leagues with managers seeking every advantage they can find. While matchups matter for every position, quarterbacks are heavily impacted by them. And though one QB may have carried your team to the postseason, a string of tough matchups might mean they’re about to fall flat at exactly the wrong time.

Case in point: Patrick Mahomes was resurgent in the early going, looking like a fantasy MVP. But managers might have gotten a preview of what lies ahead in the fantasy playoffs with a total clunker against the Texans in Week 14.

The Chiefs’ banged-up offensive line led to Mahomes posting a season-low 6.3 points against Houston. Moreover, Kansas City has unfavorable pass rush matchups in every fantasy playoff game, so Mahomes has low-floor potential throughout the playoffs. He’s probably a good start candidate for the Week 16 game against Tennessee, but in the other weeks, you may want to consider benching the former fantasy MVP. It sounds crazy, but for the playoffs you need to pull out all the stops.

Below I breakdown quarterback matchups for Weeks 15-17 with a particular focus on QBs thought of as “every-weekers” who very well should be on benches. We’ll also provide several QBs you might not think to start but who have increased value based on upcoming matchups and recent performance.

My matchup points system uses various fantasy points scored (by the quarterback) and allowed (by the opposing defense) metrics as a base. Then, variables such as the likelihood of a team getting into a high-scoring game and pass-blocking/pass-rush strength are added. These combined grades are then placed on a curve and given a 1-100 score, with 1 being the least favorable and 100 being the most favorable. As an example, Mahomes’ score against the vulnerable Titans is an 86, which is very favorable. Conversely, his score next week against the Los Angeles Chargers — who just tormented Jalen Hurts Monday Night — is 33, which is … suboptimal.

Keep in mind these grades are all based on fantasy-scoring relevance, so a defensive back who has a low yards per attempt (YPA) allowed but a high PPR fantasy points per game (FPPG) allowed will be graded as a favorable matchup in this system.

Let’s start by noting the limitations of matchup benefits. Kirk Cousins is at the top of this matchup analysis chart, but he’s obviously not someone you want to start in the playoffs. A matchup can provide a boost, but the ceiling for scoring is still aligned with the QB. In Cousins’ case, he’s definitely not an autostart with your season on the line.

There are also matchup-proof quarterbacks such as Josh Allen, Joe Burrow, Dak Prescott and Jalen Hurts, who are must-starts every week. And yes, I know what happened to Hurts Monday night. You should still plug him into your lineups for the playoffs and not think twice.

Now that we’ve categorized those candidates, along with Mahomes above, let’s look some of the biggest quarterback question marks.

Unless otherwise mentioned, the statistics below are from TruMedia/PFF, NFL Next Gen Stats or Stathead; PPR scoring is used for point totals. Roster rates are in Yahoo leagues.

Lamar Jackson, BAL

Jackson was a dud in Weeks 11-13, but a 21.6-point performance against Pittsburgh in Week 14 may signal that Jackson is back. There are potential high-scoring matchups against Cincinnati and New England in Weeks 15 and 16. The Week 17 matchup against Green Bay is another matter. The Packers have superb pass rush and vertical coverage metrics. Don’t count on Jackson as a high-percentage play in the title round.

Brock Purdy, SF

Purdy has the second-highest matchup point average. The 49ers offense could hit some big plays against Tennessee’s subpar vertical coverage in Week 15, and the Week 17 matchup against a shaky Chicago defense could turn into a high-scoring tilt. Get Purdy into playoff lineups.

Matthew Stafford, LAR

There’s no way I’m suggesting sitting Stafford for the Week 15 matchup against Detroit or the Week 17 matchup against Atlanta. The Week 16 “Thursday Night Football” showdown at Seattle is another story. The Seahawks may have the best defense in the NFL right now. That’s a matchup to avoid if possible.

Jared Goff, DET

Goff has the third-lowest rest-of-season (ROS) matchup score, but he may have more start value than that number suggests. The Week 15 matchup at the Los Angeles Rams could turn into a high-scoring affair that warrants starter status for Goff. The Steelers’ shaky pass rush can help Goff tally a solid point total in Week 16. The Week 17 matchup is what really hurts Goff’s score. The Vikings’ defense has some of the best pass rush and vertical coverage metrics. Don’t count on Goff in the championship game.

Caleb Williams, CHI

Williams has posted three games of 21+ points in the past six weeks, but he’s also tallied two games with 10.3 or fewer. Matchups against Cleveland and Green Bay in Weeks 15-16 suggest Williams will be a bust candidate in those contests. The Week 17 matchup against a 49ers defense that is terrible at rushing the passer gives Williams boom potential for the fantasy finale though.

Drake Maye, NE

Maye was a consistent 20+ point scorer earlier this year, yet he’s had only one such game in his past five starts. That may not change, since his ROS schedule score is the fourth-lowest. The only saving grace is that the Jets, New England’s Week 17 opponent, have subpar vertical pass coverage metrics. Start Maye at your own risk.

Jordan Love, GB

Love was in a scoring slump for a while, but that’s changed since the Packers’ offense started to get healthy. He has scored 19+ points the past two weeks and has a set of matchups that are the fifth-most favorable on the board. Love can also benefit from high-scoring matchups in all three games against Denver, Chicago and Baltimore. He’s someone to lock into lineups every week.

Jayden Daniels/Marcus Mariota, WSH (8% rostered)

Mariota may be filling in for Daniels if the Commanders decide to shut down their injured franchise QB. Whoever starts will benefit from the fourth-most-favorable ROS schedule. The Giants and Eagles, Washington’s opponents in Weeks 15-16, have terrible pass rush numbers. The Week 17 matchup against the Cowboys could easily kick into high-scoring mode. If the Commanders shut down Daniels, Mariota is very available on waivers and a potential fill-in candidate throughout the fantasy playoffs.

Tua Tagovailoa, MIA (18% rostered)

If you need a streamer for Week 17, look no further than Tagovailoa. The matchup against Tampa Bay is favorable across the board and rates as the best that week. During fantasy championship week, that matchup is so valuable that it makes Tagovailoa worth stashing now.

Trevor Lawrence, JAX (59% rostered)

Lawrence has posted between 19 and 21 points in all but one game since Week 6, and the consistency should continue during the postseason, as his three playoff matchups range from 42 to 65 matchup points.

Bo Nix, DEN

Nix has the most difficult rest-of-season schedule, starting with a Week 15 matchup against a Green Bay defense with very strong pass rush and vertical pass coverage metrics. Jacksonville’s defense also rates well in each of those categories. The Week 17 contest is a Thursday night game at Kansas City. Nix has posted 16.4 or fewer points in each of his past four starts. Don’t expect that trend to improve during the playoffs.

Justin Herbert, LAC

Herbert has posted 14.7 or fewer fantasy points in four straight games. That scoring pace isn’t likely to change with a ROS schedule strength score that ranks in the bottom 10. The only saving grace for Herbert may be if the Week 16 game against Dallas turns into a high-scoring affair.