How predictive were poor preseason performances in 2017?

Let’s just say it. That was likely the worst Detroit Lions preseason performance we’ve seen in some time... maybe ever. From Game 1 to Game 4, the highlights were few and far between, and the Lions looked overmatched in just about every single quarter of every single game.

They were outscored 111-77. They were outgained 1401-1125.

And the differences were even more drastic when you focus on the players that actually may still be around next week. In the first halves of each game, the Lions were outscored 68-16. The Lions’ first string offense scored a total of nine points in eight drives, while the starting defense gave up 31.

But how much should the Lions be worried? Backup quarterback Matt Cassel knows the preseason can be very misleading.

“I’ve been through a lot of different preseasons over my 14-year career. There has been teams where we are 0-4 and look like a disaster and we end up going 11-5,” Cassel said after Thursday’s loss to the Browns.

And he isn’t exaggerating. In 2008, the New England Patriots went 0-4 in the preseason, getting outscored 89-56 in four games. During the regular season, even after losing Tom Brady in the first game of the regular season, Cassel still led the Patriots to an 11-5 season (though, they actually missed the playoffs that year).

And just looking at last year, performances varied wildly from preseason to regular season.

The Lions’ defense was especially bad this preseason, so let’s take a look at the really bad defenses from the 2017 preseason. Here are the bottom five in terms of scoring defense:

32. Patriots (31.5 PPG)
31. Chargers (25.8 PPG)
30. Giants (24.8 PPG)
29. Dolphins (24.5 PPG)
28. 49ers (23.8 PPG)

Now let’s look at where those five teams finished in the regular season:

Patriots: 5th (+27), 18.5 PPG (-13)
Chargers: 3rd (+28), 17.0 PPG (-8.8)
Giants: 27th (+3), 24.2 PPG (-0.3)
Dolphins: 29th (no change), 24.6 PPG (+0.1)
49ers: 25th (+3), 23.9 PPG (+0.1)

You can see there’s very little correlation. While the Dolphins and 49ers finished with similar stats in the regular season, the Patriots and Chargers were far better in the regular season.

Now let’s look at the best five defenses from the 2017 preseason:

1. Browns (7.2 PPG)
2. Ravens (8.0 PPG)
3. Saints (10.2 PPG)
4. Broncos (12.5 PPG)
5. Seahawks (14.0 PPG)

And how did those teams finish in the regular season?

Browns: 31st (-30), 25.6 PPG (+18.4)
Ravens: 6th (-4), 18.9 PPG (+10.9)
Saints: 10th (-7), 20.4 PPG (+10.2)
Broncos: 22nd (-18), 23.9 PPG (+11.4)
Seahawks: 13th (+8), 20.8 PPG (+6.8)

All five teams clearly game up a lot more points per game during the regular season. And while some remained a top 10 defense, others fell significantly.

That’s all to say, the preseason holds almost no predictive value for regular season defensive performances.

Of course, that doesn’t mean there shouldn’t be some worries. The Lions didn’t get much inspiring play from the players they expect to be starters. Detroit didn’t have a cornerback not named Darius Slay play well during the entire preseason. The defense didn’t notch its second sack of the preseason until there was only two minutes left in the finale. The offensive line depth looks much thinner than previously hoped. And hopeful candidates to improve this year—Jarrad Davis, A’Shawn Robinson, Teez Tabor and Michael Roberts—have all severely underwhelmed this August.

These are all legitimate concerns to have entering the 2018 season, but what’s important is that the concerns going in are not always the concerns coming out. Let’s hope this is the case moving forward.