On Aug. 30, 2016, as Teddy Bridgewater's left knee gave way during the final practice of the Vikings' preseason, the team's window to build a contending roster with the luxury of a cheap quarterback met its end at least two years early.

The Vikings sent a first- and fourth-round pick to the Eagles for Sam Bradford four days later, taking on his $7 million deal for 2016 and $18 million contract for 2017 out of the belief they could keep a championship bid together with the right QB.

Bradford gave way to Case Keenum, and then to Kirk Cousins, as the Vikings kept doling out megadeals to their draft picks (largely on the defensive side of the ball) to hold the core of the roster together.

The Vikings' decision to part with longtime starters Everson Griffen, Linval Joseph, Xavier Rhodes and Trae Waynes this offseason signaled what General Manager Rick Spielman termed "an evolution of the roster," with a 15-player draft class seemingly shaping expectations that the 2020 season would be something of a transition.

But then on Sunday, four years after the Vikings officially began their attempt to win with both a market-rate quarterback and high-paid defensive players, they struck an early-morning deal that signals their focus remains on the here and now. They sent a second-round pick and a conditional 2022 fifth-rounder to Jacksonville for Yannick Ngakoue, a former Pro Bowl defensive end who took a nearly $6 million pay cut to play the 2020 season in Minnesota for $12 million.

Ngakoue, like Danielle Hunter, is still only 25, and the two could form the Vikings' next great pass-rushing tandem for the rest of Spielman's and coach Mike Zimmer's time together in Minnesota.

Zimmer said on Sunday the Vikings had been pursuing another pass rusher for a while; sources said the coach was a prominent voice in the effort to bring back Griffen before he signed with the Cowboys.

The Vikings rarely use a heavy volume of blitzes, relying instead on a disruptive four-man rush. If they needed another data point to reinforce their strategy, they needed only to look at the game that cost them a chance at the NFC North title (a Week 16 loss to the Packers) or the one that ended their season (their divisional playoff defeat in San Francisco). According to Pro Football Focus, Green Bay pressured Cousins on 17 of his 36 dropbacks while blitzing him just once; the 49ers needed just six blitzes to pressure Cousins on 17 of his 35 dropbacks.

Because Ngakoue didn't sign his franchise tag, the Vikings can't finish a long-term deal with him until after the season. It strains credulity, though, to think they would have made the trade without intentions to keep him around after this year.

They can place the franchise tag on him again next year, or work out an extension on their own terms next spring. To do so, though, they'll have to deal with a set of now-familiar financial constraints that come with a unique twist this time around.

A lack of fans in the stands this season could mean a lower salary cap for the 2021 league year; a cap in the range of $175-$185 million would be tricky for the Vikings, who already have $186 million committed to players on their 2021 roster without deals for Ngakoue, Anthony Harris or Dalvin Cook.

After Myles Garrett and De'Marcus Lawrence got new deals from the Browns and Cowboys this offseason, edge rusher became the only position in football other than quarterback with more than three players making at least $20 million a season. A big season in Minnesota could give Ngakoue a case for a similar deal. A lucrative contract for Ngakoue could give Hunter's camp reason to argue he deserves the same; his deal ranks only 18th in the league among edge rushers.

The Vikings broke off tense negotiations with Cook's camp earlier this month, and their ability to reward him with upfront cash while keeping his salary cap number in check might be gone now that they'll need much of the operating room created by a likely move with Riley Reiff (either a release or a restructured deal) just to get through the 2020 season.

And then there's the matter of Cousins, who's scheduled to count $31 million against next year's cap and trigger a $35 million salary for 2022 if he's on the roster by the third day of the 2021 league year.

His deal is effectively set up to force a decision from the Vikings after this year; if they're planning to keep him on the roster past 2021, they could be headed toward a reworked contract that would reduce his 2022 cap number from $45 million — currently the highest in the league for a quarterback that year by more than $3 million.

The Vikings, in effect, are trying to maintain a roster of high-priced defensive talent and explore a long-term deal for a running back while keeping one of the NFL's most expensive QB contracts on their books.

It's a tenuous line they've managed to walk for several years. When they signed Cousins in 2018, for example, sources said decisionmakers knew it meant they would be unable to sign either Eric Kendricks or Anthony Barr. The team got a deal done with Kendricks a month later, letting Barr get to the point of a verbal agreement with the Jets. He had second thoughts and the Vikings worked out a deal to keep him, making room under their salary cap by restructuring Griffen's deal minutes before his base salary was set to be guaranteed.

Trying to traverse the Vikings' current course while a pandemic jolts the NFL's economic engine is trickier still.

Zimmer — coaching on a new three-year extension this season — has smirked at the idea the Vikings are rebuilding in 2020, and the trade for Ngakoue sends a message about the team's present intentions as well as its future plans. The Vikings are trying to reload as they go; they've been nowhere near a full rebuild, and they've shown no intention of returning to the realm of a young, cheap QB — along with the patience it requires — since Bridgewater's knee collapsed four years ago.

They've made three trips to the playoffs in six years with just two Pro Bowl appearances from their quarterbacks during that time. It's an unusual course — remaining in win-now mode with something short of transcendent quarterbacking — and the Vikings have stayed on it with bountiful resources from ownership and financial ingenuity from their front office.

Maintaining it in the years to come might require even more of those things.