Question: What happens when a single-high defense doesn’t have a legit single-high safety?

Answer: It gets torched on a regular basis, even against lesser talent like Andy Dalton (benched by the Bengals) and Matt Schaub (a backup who made his first start since 2015).

For nine weeks in 2019, the Seattle Seahawks defense wasn’t good. Period. The team was still 7-2 solely because of Russell Wilson’s MVP-level heroics. But it wasn’t sustainable – the rope-a-dope strategy that kept the Seahawks just barely above water was a mirage more than a reliable formula. Seattle lost a pair of home games to some of the league’s elite teams: the New Orleans Saints (even without Drew Brees) and the Baltimore Ravens.

There was a reason why the Seahawks were 6.5-point road underdogs to the 49ers in Week 10 – because the defense had shown nothing to suggest that a significant step forward was in the cards. The pass rush was non-existent and the secondary was leaky at best. If Seattle couldn’t beat good teams at home, why on earth would it be able to beat the undefeated 49ers on the road?

The last two games have been an entirely different story. Not only did the Seahawks win back-to-back road games against the 49ers and Eagles, but it was the defense that definitively put the team on its back.

And the common denominator has been Quandre Diggs’ insertion into the lineup at free safety.

“He’s doing stuff. He’s doing stuff. I’m really excited about him,” Pete Carroll said after Seattle’s 17-9 win in Philadelphia on Sunday. “I think as a good player who’s got experience wherewithal and all that helps other players. He’s doing it – the confidence that comes from knowing that he knows the game and knows what’s going on.”

In Diggs’ two starts, the Seahawks have allowed just two offensive touchdowns (one in each game), they’ve posted eight sacks and generated eight takeaways. That’s no coincidence.

“He’s a true redline to redline (player),” Bobby Wagner said. “He’s fast enough – if they try to throw it over his head on a corner – he’s fast enough to get there. I think that gives everybody confidence. Everybody trusts him. He’s been a great addition to us.”

There’s a reason why Carroll values having a veteran at free safety and why Earl Thomas was such a lynchpin to Seattle’s dominant defenses over the last decade. You could already argue that Diggs is a top five most valuable player on the Seahawks roster given the importance of his role and his collective impact on the defense. The nickname for the position is literally “The Eraser,” which requires the physical ability and mental capacity to clean up the mistakes of others.

When other players know they have that safety net, it allows everyone to play faster, be more aggressive in their assignments and even take a few chances if they feel like they know what’s coming. Notably, K.J. Wright said Seattle’s defense was all over Philadelphia’s offensive tendencies on Sunday.

The overall speed of the defense has been evident over Seattle’s last eight quarters of football.

“Quandre is the man,” Wright said. “I’m glad he’s on this team. Ever since he came here, somehow we’ve just been playing super dominant. We’ve got a bad man in the middle of the field, just running redline to redline; making big hits. It can make a statement for your defense.”

Seattle tried to mix in some single-high looks earlier in the season and got burned regularly. John Ross’ 55-yard touchdown just before halftime in Week 1 against Tedric Thompson is a play that comes to mind. Marquise Blair wasn’t ready for the responsibility of the position, either.

That’s why the biggest benefactor of Diggs’ presence is Bradley McDougald. Prior to playing alongside Diggs, McDougald played as a two-high safety predominantly and even had to play free safety at times.

Now the traditional strong safety is back to doing what he does best, solely because Diggs was able to take so much off of his plate.

“I have found myself being able to play one position, staying in closer (to the line of scrimmage); doing my job,” said McDougald, who had six tackles and intercepted Carson Wentz on Sunday. “I’ve got less to worry about – less getting people lined up. It’s just less. I can focus on me. That’s the best position to be. I’m moving faster.”

Carroll was ecstatic about Seattle’s safety play in the win against the 49ers and had similar sentiments after beating the Eagles. He noted the sideline conversations and in-game adjustments between Diggs and McDougald that have been so crucial.

“They’re really balling,” Carroll said.

Diggs had an interception in his Seahawks debut against the 49ers and had a hand in another takeaway in Philadelphia, recovering a Dallas Goedert fumble. He may have forced the fumble, too, but the official game stats credited it to Shaquill Griffin. Diggs' 88.4 Pro Football Focus grade was the highest of any Seahawks player against the Eagles.

What’s important is that he’s added a noticeable confidence to everyone on Seattle’s defense, even its most senior members.

“Everyone is moving well together,” Wright said. “It feels good. It feels natural. I love playing with him.”

It’s hard to believe that the Seahawks were able to acquire Diggs for a mere fifth-round pick because his impact has been so vast and so immediate. And this isn’t to minimize the strong play from others: Jadeveon Clowney absolutely dominated the 49ers from start to finish, Shaquem Griffin’s speed has been a shot in the arm to the defense and Ziggy Ansah had 1.5 sacks against the Eagles in what was easily his best game of the season.

But it doesn’t seem to be an accident that it’s all clicked upon Diggs entering the lineup. The veteran safety has changed the entire complexion of Seattle’s defense and thus raised the ceiling of what this team is capable of in 2019.

The early season smoke and mirrors are gone, and the Seahawks are now a legit Super Bowl contender.

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