The Vikings upgraded their audio system around the outdoor practice fields at the TCO Performance Center before the 2023 season, mounting speakers to the light towers surrounding the fields so they could hear audio in surround sound. They use the system to play music as players warm up at the beginning of practices, but it was first installed to better simulate the challenge of communicating over a gameday din.

Teams have practiced with crowd noise for years; the Vikings used to do it by wheeling a stadium-sized speaker down the sideline and aiming it at the line of scrimmage. Most teams do it to prepare for menacing road environments. The Vikings are one of the few teams who use it before home games.

"Seattle," said cornerback Shaq Griffin, now on his fifth team in eight seasons. "That was the only time where it happened."

A deafening crowd and a dominant defense, when combined, can create a downburst so powerful that it transforms the landscape of a football game. Griffin began his career in Seattle after the heyday of the Legion of Boom, but he still played with enough of the Seahawks stars like Earl Thomas and Bobby Wagner to know what it could feel like. The fact the Vikings won just two times at home last year — one fewer than even the 2020 season when U.S. Bank Stadium was empty — grated on coach Kevin O'Connell particularly because he knew what they were missing.

"If we can get off to good starts, if we can protect the football, force some turnovers, have our fans feel the momentum of their role on third down, it just kind of feels like a tidal wave of momentum," O'Connell said. "And our players feed off of it."

The Vikings' 34-7 victory over the Texans on Sunday reached its most farcical point in the second quarter, with Houston trailing 14-0 and quarterback C.J. Stroud trying to communicate countermeasures against the Vikings defense. Noise levels that topped 125 decibels Sunday rattled tympanums and wore on nerves; the Texans committed false starts on three straight plays to fall out of field-goal range, as even referee Shawn Hochuli announced the infractions with a touch of disbelief in his voice.

It was there, at the game's most absurd moment, that the truth about the 2024 Vikings became the most clear: A defense with this level of mayhem, playing off the boost of an environment this frenzied, can be a powerful thing.

The Vikings made Stroud, the NFL's 2023 Rookie of the Year, the second quarterback this season who could count his team's point total with fingers to spare. He had thrown five career interceptions before Sunday; he left U.S. Bank Stadium with the second multi-interception game of his career, giving way to Davis Mills for mop-up duty after the Vikings had sacked him four times.

Houston ran for only 38 yards and went 4-for-14 on third downs. Of the Texans' 11 penalties, eight were on the offensive line. Left tackle Laremy Tunsil alone was penalized five times: three times for false start and twice for illegal formation after setting up a step deep in the backfield.

The Vikings all but eliminated the Texans' potent downfield passing game, allowing only one deep throw while Stroud was still in the game. A week after San Francisco 49ers quarterback Brock Purdy greeted Brian Flores at midfield by telling the Vikings defensive coordinator that his "scheme was crazy," Griffin said he had Texans receivers asking him to stop playing a certain coverage, only to name the incorrect one.

"Every time I had a receiver lined up against me, he tried to guess what coverage [we were in]. He guessed wrong," Griffin said. "We've got guys who tell us when they're sitting there, huddling up and making their plays, that they're confused."

It turned the Vikings-Texans game, one of only two NFL matchups Sunday between undefeated teams, into a rout. The Vikings, one of four NFL teams at 3-0, won by their biggest margin since a 29-point victory over the Los Angeles Chargers in 2019 and scored their biggest home victory since the 34-7 win over the Cincinnati Bengals that helped them clinch the 2017 NFC North title.

They deferred after winning the opening coin toss, content to play on their pregame hypothesis that for all Stroud's early success, the young quarterback had yet to face the kind of NFL adversity that would prepare him for the U.S. Bank Stadium cauldron. Texans tight end Cade Stover was called for holding on the first offensive play; on the next play, Harrison Phillips batted Stroud's first pass in the air for a Kamu Grugier-Hill interception.

Sam Darnold threw the first of his four touchdown passes six plays later, rolling to his left and finding Justin Jefferson for a 6-yard score after the receiver peeled away from safety Eric Murray.

"Huge spark, for our defense to go out there and create a turnover on the first drive," Darnold said. "And then for us to go out there and capitalize, that kind of set the tone for the whole game."

The Texans' next drive ended when Jonathan Greenard, who'd signed with the Vikings in March while Houston pursued Danielle Hunter in free agency, ran over Stover for the first of three sacks against his former team. Ka'imi Fairbairn, who'd made 17 of his last 18 field-goal tries of 50 yards or more, pushed his 54-yard attempt wide right; Darnold hit Aaron Jones for a touchdown six plays later, on a call that sent Jefferson out of the backfield on a route that pulled linebacker Azeez Al-Shaair toward the sideline to clear space for Jones.

BOXSCORE: Vikings 34, Houston 7

NFL standings

Minnesota's lead reached 21 points in the third quarter before Houston would score on a Stroud-to-Cam Akers touchdown. The Vikings would then drive for two more Will Reichard field goals, bisected by Darnold's 2-yard scoring pass to Johnny Mundt.

It was the first time since 2021 that Darnold had led a team to three straight wins. The quarterback who'd signed with the Vikings on a one-year deal leads the NFL in touchdown passes through three weeks and caused a stir Sunday when he briefly left the game with a right knee injury after Hunter earned the first roughing penalty of his career on a play where he was blocked into Darnold's leg.

Darnold returned to the game after one Nick Mullens handoff. He said he would get his knee examined Monday but added he felt good enough to go back in the game. He returned to a roar from the U.S. Bank Stadium crowd and a brief chant of "Sam-my, Sam-my, Sam-my."

"It meant everything," he said. "Not only that, but my entire time here in Minnesota has been amazing with the fans."

They roared for Darnold, for a defense that started five players it signed as free agents this summer, for a team that began the season with little fanfare but has stormed to the top of the NFC through three weeks while outscoring opponents by 55 points. Ears, no doubt, were still ringing in the home locker room after the game when O'Connell told his players: "It feels real to me, fellas. We are capable of absolutely anything that's out in front of us right now."

Their next test will be a trip to Lambeau Field, either to face Jordan Love or a Green Bay Packers team that's cultivated an offensive formula without him. After that, the Vikings will end their four-contest slate of games against young quarterbacks and head to London to face the Jets for their 30th, and perhaps final, regular-season matchup against Aaron Rodgers.

As fans departed Sunday afternoon, the message on the U.S. Bank Stadium video board advertised the Vikings' next home game, on Oct. 20 against the Lions. Last Dec. 24, Detroit won its first division title in 30 years at U.S. Bank Stadium. The Lions' next trip to Minnesota could be critical to the NFC North race.

The Vikings, to the surprise of most outside their practice facility, appear to be part of that race. After a 27-point victory Sunday, the tepid preseason predictions seemed like little more than chatter to a team that's proved capable of making noise of its own.

"We're getting stuff done every day," safety Harrison Smith said. "There's a lot of purpose, with joy, a determined mindset throughout the week. It's not like, 'We've got to go to practice; we've got to go to meetings.' There's none of that, because we're doing stuff we all believe in. I wake up, and I enjoy going to work. I think pretty much everybody does."

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