The first draft choice Rick Spielman made, with full control of the Vikings' roster as their general manager, was to select USC tackle Matt Kalil fourth overall in the 2012 draft. Kalil, the Vikings hoped, would become a decade-long fixture at left tackle; he made the Pro Bowl in his rookie season, as part of a Vikings line that thrived blocking for league MVP Adrian Peterson on a surprise playoff team.

All five Vikings linemen started all 16 games that season, and three of them got paid as a result: the Vikings ponied up extra money to keep the Bears from snatching right tackle Phil Loadholt in free agency the next spring, and doled out extensions to guard Brandon Fusco and center John Sullivan in the following years. During a press conference in 2016, while referencing a Vikings study that showed highly-drafted linemen tended to turn into better players, Spielman held up Fusco and Sullivan as examples of how the Vikings had found success bucking the trend.

And for years, they tried. Kalil was the only lineman the Vikings took in the first two rounds from 2012-17; he and Loadholt were the only first- or second-round linemen selected during Spielman's first 11 drafts with the team. The Vikings, instead, tried to fortify their line with free agents like Alex Boone, Andre Smith, Mike Remmers and Riley Reiff, while hoping they could hit on Day 3 picks like Sullivan and Fusco or under-the-radar pickups like Joe Berger, Nick Easton, Mike Harris and Jeremiah Sirles.

"We got Easton from San Fran, we got Sirles from Nebraska, I'm always going to try to keep shuffling these offensive linemen in," Spielman said several weeks after the 2015 season. "To me, if you can just keep flinging through here, Mike Harris was a claim guy when he got released from San Diego, so you got to constantly turn that position over and constantly keep finding the right combination of guys. And I don't know, we let some guys out of here that have played too, went on to play. ... To me, a skill guy or a running back can automatically, maybe, make a bigger impact because they can rely on their athletic skillset to do that. An offensive linemen is usually not the same because they are working with five and you can't just rely on your athletic ability like you can at some of the other skill positions."

But injuries derailed the careers of Kalil and Sullivan in Minnesota, while Fusco never returned to his stellar 2013 play after a torn pectoral muscle in 2014. Boone lasted just a season in Minnesota and Remmers was released after shifting from tackle to guard.

And in recent years, the Vikings' philosophy about building their line has changed significantly.

Their selection of Christian Darrisaw with the 23rd overall pick on Thursday night — after Spielman traded down nine spots from No. 14 and considered moving back up — was the fourth draft pick the Vikings have used on a lineman since 2018. That's the most in the NFL; no other team has drafted more than two linemen in that time (though the totals could obviously change in the second round tonight).

Their 2021 line figures to consist of Darrisaw, center Garrett Bradbury (a 2019 first-round pick), guard Ezra Cleveland (a 2020 second-rounder) and tackle Brian O'Neill (a 2018 second-rounder). The Vikings still have a hole at left guard, but have four picks in tonight's third round and could decide to fill it with another draft pick.

They have invested heavily in an effort to fix what's been their biggest problem on offense for years; the question now is whether it will work.

In Darrisaw (who stands 6-foot-5, weighs 322 pounds and has 34 1/4-inch arms), the Vikings added a player with the size to play left tackle, where the Vikings ultimately haven't tried Ezra Cleveland after drafting him as the heir apparent to Reiff last year. Darrisaw has played in a zone scheme at Virginia Tech, and should fit the Vikings' approach there, but he stands out on a line that's been constructed with leaner players who could reach linebackers in the running game.

"We feel like we're athletic but you end up going against some really big defensive linemen, especially inside, you get so many of those big guys," Zimmer said. "Darrisaw has real long arms, so that helps him in pass protection against some of those speed rushers. But yeah that was one of the things we talked about.''

Bradbury has struggled to handle effective pass-rushing tackles, and faces a critical 2021 season with a decision on his fifth-year option looming next spring. O'Neill could be in line for a contract extension before this season and has turned into a solid pass protector, but Cleveland gave up four sacks in December, as the Vikings' playoff hopes crumbled, and will need to improve in his first full season as a starter.

Heading into what could be a make-or-break year for their current regime, the Vikings are betting on their group of highly-drafted linemen coming together.

"He'll be a left tackle," Zimmer said of Darrisaw. "But he's got to come in and compete and win the job just like everybody else. We'll be able to keep O'Neill at right and go from there."

Spielman said the Vikings started making phone calls about trading up as soon as the fourth overall pick on Thursday night; he wouldn't divulge the Vikings' targets, but Oregon tackle Penei Sewell and Northwestern tackle Rashawn Slater were believed to be at the top of the Vikings' board (there was some thought around the league the Vikings could pursue Ohio State quarterback Justin Fields as he fell down the draft board, though their interest level must not have been enough to acquire the 11th pick and keep him from the Bears, who moved up nine spots to draft him).

Analytics would suggest there are more efficient ways to use first- and second-round picks than by spending them on offensive linemen, particularly interior linemen. But the Vikings' recent investments — triggered either by a reaction to problems from the past or an adherence to their own studies about hit rates on top picks along the offensive line — have taken them on a different course up front.

Particularly in pass protection, where Darrisaw might be the Vikings' most significant investment since Kalil and where they've longed for more consistency in front of Kirk Cousins, they need it all to deliver results.