This is a tough game for the Chargers. The New England Patriots, even with their hiccup in Green Bay, have been on a tear. The game plans from their coaching staff often appear novel and intelligent, so San Diego will need to have a great game plan on offense and defense and execute it nearly flawlessly.
First, looking at New England’s team level metrics trended over recent years you see remarkable consistency. Since 2008 (and including their year-to-date performance) and onwards they have not ended a season with Football Outsiders DVOA below 20%, averaging over 30%. In contrast, San Diego has been above 20% only twice during that same time period, averaging 10%.
I include the PFFM (metrics derived from Pro Football Focus' data, methods outlined here) for reference and they typically are strongly correlated, though I trust DVOA much more. One thing to note, is that PFFM has consistently liked New England’s defense, something to keep in mind when I drill down on the positional strength using PFFM.
So New England is consistently good. But this is the team that was pummeled by Kansas City earlier in the year, so perhaps they are not very consistent, potentially allowing San Diego to catch them in an off week.
The data above shows the components of DVOA (offense, defense) along with the total for each game New England played. The dotted black line is their cumulative DVOA score for the season after each game. The DVOA by game data shows remarkable consistency, even with the Kansas City drubbing included, but a strong upward trend following the Kansas City game. Even the loss in Green Bay had solid metrics. So there are not a lot of off weeks for New England.
In contrast, San Diego has been much more erratic. They, though the trends since the Miami game have generally been upward.
Looking at their total DVOA by game shows San Diego starting strong, fading as injuries and questionable game plans dragged them down, eventually bottoming out in MIA in week 9. Since then, San Diego has been playing better. New England also has had a solid upward trend, even including their loss to Green Bay in week 13.
If you added a trend line for San Diego for the whole season, it would be flat. For Chargers fans, the most hopeful trend is week 9 and later.
Drilling down into the positions using PFFM, New England looks a lot like San Diego, just better.
On offense, both teams have excellent quarterbacks but not too much else supporting them. New England’s line looks like less of mess than San Diego’s has been, both have positive scores for their receiving corps. PFFM likes New England’s backs more than San Diego’s, though there would be much less of a gap had Ryan Mathews had more than 137 snaps so far this year (vs. Donald Brown’s 251).
On defense, they look similar as well, with their strength being in their secondary, decent LB metrics (much better than San Diego’s) and both have bad metrics for their defensive lines. Remembering back, their defense looked better on PFFM than it did on DVOA. DVOA rates New England’s defense as average, while PFFM considers them notable above average.
However, even adjusting for any potential New England bias in the defensive scoring, their defense looks similar but better. For the Chargers to have a shot at slowing down New England, the Chargers’ defensive coordinator may need to introduce different looks and game plans than have been presented thus far. Drilling down on just the Chargers’ defensive DVOA scores by game (metric inverted, so a good score, normally negative, is shown as positive), you do not see any good games against good offenses:
In terms of individual contributors for New England, their top scores belong to their best known players: Brady, Gronkowski and Revis. But as outlined earlier on this site, New England is a team that gets good production from non-star players:
The "Player PFFM" is essentially how many standard deviations their PFF score was vs. the scores for their position. The "Team PFFM" takes their score but weights it by how important the position is.
The players that struggle mostly come from their defensive line and other cornerbacks who are not Revis or Arrington and some interior linemen.