Fantasy football Week 18 shadow report: Key WR/CB matchups

Cooper Kupp and Odell Beckham Jr. should be upgraded against a 49ers secondary that has struggled late in the season. Photo by Rob Carr/Getty Images

By using our play-by-play data, we're able to identify defensive schemes and where each wide receiver and cornerback lines up on each play. By tracking these WR/CB matchups, including potential shadow situations, we can offer the best projections, rankings, sit/start decisions and fantasy advice each week. Fantasy football is a weekly game, so knowing the matchups can also help you make the best waiver wire pickups.

Below are the receivers with the best and worst matchups this week, as well as the corresponding fantasy impact.

To view the primary defenders the top three wide receivers for each team will see this weekend, be sure to check out our weekly WR vs. CB cheat sheet.

Unless otherwise noted, references to where teams rank in statistical categories adjust to a per-game basis to avoid distortion due to bye weeks.

Advantageous matchups

Rams' Odell Beckham Jr., Cooper Kupp and Van Jefferson vs. 49ers' Josh Norman, K'Waun Williams and Ambry Thomas

The 49ers' perimeter woes continue, as they've now allowed the third-most fantasy points to boundary receivers over the past eight weeks and the fifth most over the past month. They're also allowing the sixth-most fantasy points overall to receivers over the past eight weeks. Norman and Thomas have struggled out wide, and they'll have their hands full with Beckham (79% perimeter) and Jefferson (66%) this week. San Francisco has been average against the slot, but Kupp (65% slot) posted an 11-122-0 receiving line on 13 targets in the first meeting between these teams, with most of that damage against Williams. Jefferson (3-54-0) was fairly quiet in that game, though Emmanuel Moseley (now on IR) covered him on one-third of his routes. Beckham ran only 10 routes in what was his team debut. Upgrade the Rams' receivers across the board.