On the surface, the Raiders pass defense doesn’t look that terrible. Oakland has allowed 2,920 passing yards, which is actually slightly above average (14th fewest in the NFL). Opposing passers are completing just 62.9% of passes against Oakland, which ranks as the 8th best mark in the NFL. Even in interceptions, where the Raiders are below average, the defense’s 9 interceptions still ranks tied for 21st in the league. So bad, but not particularly noteworthy.

But there are three places where Oakland’s pass defense looks really, really bad.

• The Raiders have just 10 sacks this season and a 2.8% sack rate; both marks are easily the worst in the league. Only four teams ever have had a sack rate below 3.0% for a full season: the 2008 Chiefs (1.9%), 1981 Colts (2.6%), 2009 Jaguars (2.7%), and 1958 Packers (2.9%). There are 9 players this year with more than 10 sacks, and Khalil Mack (9 sacks in 10 games) is averaging more sacks per game than the entire Raiders defense (10 sacks in 12 games).

• Opposing passers are averaging 13.76 yards per completion this season.  In the modern era, the average yards per completion has been declining for decades.   The Lions are allowing 12.5 yards/completion this year, the second worst rate in the NFL. How bad has Oakland been? The last time a pass defense allowed this many yards per completion was the 1990 Patriots.

• The Raiders have allowed 29 touchdown passes, the most in the NFL.  That’s despite facing just 345 pass attempts, the fewest in the NFL.  That’s remarkable and it is because Oakland has allowed a touchdown pass on 8.4% of all passes.  That’s the worst rate of any team since the 1967 Dolphins.

Oakland has allowed 8.7 ANY/A this year, which puts the Raiders in shouting distance for the worst pass defense ever (without adjusting for era, of course). That mark is currently held by the 2015 Saints.