The Vikings drafted Josh Metellus in 2020 as a safety. Their depth chart, which conforms neatly to a long-used, mass-produced template, still lists him as one.

Metellus no longer uses that title, instead offering a one-character name for his position that's both more succinct and more complex than what's printed in a game program. In algebra, it could be a variable; in cryptography, it could be a cipher.

"We call it 'all X's,'" he said. "We're all 'X's' on the field. Coach tells us what to do; we line up in that spot and we get it done."

Metellus has become something close to a positionless player during his first year in a Brian Flores defense that's used unconventional means in an attempt to end four years of unsettling Vikings results.

On one play, Metellus might be engaging a left tackle while rushing off the end of the line; on the next, he might be blitzing as a linebacker or covering a slot receiver. Pro Football Focus, which charts players' position alignments on a snap-by-snap basis, lists him as having played 12 this year: strong safety, free safety, left cornerback, right cornerback, slot cornerback, left inside linebacker, right inside linebacker, middle linebacker, left outside linebacker, right outside linebacker, right defensive end and left defensive tackle (the final two for a snap each).

In the Vikings' 19-13 victory over the Bears, he was on the field for 59 snaps, spending 28 in run defense and 22 in coverage while rushing Chicago quarterbacks nine times, including when he beat Bears left tackle Larry Borom on his way to the strip sack that set up Jordan Hicks' 42-yard fumble return for a touchdown that ultimately decided the game.

At Michigan, Metellus played strongside linebacker as well as safety as a freshman. The rest of his college career, he lined up primarily in the slot. "I'm the type of player that adapts to certain situations," he said, "but I've never done nothing like this. This is crazy."

The Vikings have shown little use for orthodoxy in their first year with Flores, who replaced Ed Donatell as coach Kevin O'Connell searched for a defensive coordinator who would add punch to a unit that allowed the second-most points and fifth-most yards in the NFL last year. They have blitzed opposing quarterbacks 57.9% of the time this season; the only other team to blitz more than 50% of the time in the past six years, according to Pro Football Reference, is the 2019 Ravens at 54.9%.

Metellus leads NFL defensive backs with 45 pass rush snaps, and safety Harrison Smith is second with 40, according to Pro Football Focus. No other defensive back has more than 28. Smith, the 12th-year safety, could set a single-season high for pass-rush attempts if he goes after 49ers quarterback Brock Purdy five times on Monday night. Hicks, the Vikings' ninth-year linebacker, has rushed 66 times in 405 snaps; his 16.2% pass rush rate is higher than any Anthony Barr had in eight seasons with the Vikings.

"Sometimes, somebody's going to come and you're going to be like, 'Oh — that's different,'" linebacker Danielle Hunter said. "We like it. And it's worked out for us so far."

Through six games, the approach has coaxed modest improvement out of a young defense installing its third scheme in four years. The Vikings rank 12th in the league in yards against and 17th in points against. They have increased their pressure rate from 19.5% to 23.6% and are tied for ninth with 18 sacks. And while they have given up 18 pass plays of 20 yards or more — tied for the 12th most — they are giving up big plays through the air less frequently than last year, when they ranked 31st with 61 pass plays of 20-plus yards.

"We have given up some big plays on some of those pressure looks, but we've also kind of talked people out of taking a few more of those shots," O'Connell said. "I'm looking back on the game last week, and we're really in the similar look on all three turnovers: the strip sack return from Hicksy, the interception by Hicks, and then Byron [Murphy]'s end-of-the-game interception. We're all kind of on the same look and we got it blocked three different ways with some effectiveness by our guys, affecting the quarterback on all three plays."

Building from Flores' repertoire

Ingenuity could be crucial for the Vikings on Monday night, when they play host to the 5-1 49ers in their first of at least four games without edge rusher Marcus Davenport, who is on injured reserve because of a high ankle sprain. Purdy, in his second year, has been blitzed 45.1% of the time this season (the second-highest rate in the league, according to Pro Football Focus), but he has a 101.6 passer rating against the blitz.

"You've got Kyle sitting there, and he's done this for a long time," said Flores, referring to 49ers coach Kyle Shanahan. "He's seen every front structure, every coverage concept, every blitz. He's got an answer for all those. They have a very good scheme. Part of that, for us, is we're going to have to play fast. We're going to have to play physical. We can't be sitting there thinking about what to do, or be mesmerized by every shift, motion, jet, orbit."

To answer Shanahan, Flores will consult his own deep catalog of pressures, in search of looks the Vikings hope offenses aren't prepared to handle.

"We want it to be where teams don't know if we're sending everybody or we're dropping eight, or if we're sending half on this side or the other half," Metellus said. "We want that confusion on offense. We want them to play slow and us to play faster."

As Metellus recalled this week, Flores began the Vikings' first defensive meetings this spring by telling players he planned give them everything in his repertoire, from pressure packages to coverages, and see what they retained. The concepts they grasped would become the defense's foundation, and the Vikings would build from there.

The iterative process invigorated Smith, who returned to the kind of multifaceted role he had enjoyed under Mike Zimmer. And it empowered Metellus, once Flores saw the football acumen and inquisitiveness that teammates and secondary coach Daronte Jones had praised.

"Did I know right away? No. You never really know," Flores said. "But it didn't take me long to see he was smart. He understood the game conceptually. … From a capacity standpoint, he understands the game almost at a coach's level, whether it's coverage concepts, run game, adjustments and fronts. We can put a lot on there. We just continue to add more, and it hasn't been an issue."

Metellus had long been fascinated by how pass rushers did their jobs; since he has been asked to take on tackles more frequently, he has approached Hunter for advice.

"I think a big thing I've been interested in lately is knowing what protection we're going to get," Metellus said. "Before, I was walking into it blind, because as a safety, you're usually coming free, because they're not expecting it. Now that I've been in it so many times, they're expecting it. So now I'm noticing the protections, and what I can do to help somebody else be successful instead of me just having to beat my guy."

Up next: Blitzing Brock

Metellus' emergence alongside Smith has given the Vikings another versatile piece with which to antagonize quarterbacks. Sometimes that's done by showing a seven-man rush and dropping several players into coverage once offenses have devoted a blocker to a particular rusher, or having rushers drop into coverage after "tagging" a blocker (a favorite technique of assistant coach Mike Pettine). Frequently, it's done by sending enough pressure to try and overwhelm a blocking unit, though Flores said, "When people talk about blitz percentages, I may see it a little bit differently.

"There's run pressures, there's max blitzes, there's blitzes, there's fire pressures. There's fire zone [blitzes]. We've done all of them over the course of the year. … In my mind, there's run pressures, and then there's pass situation pressures. If you call a run pressure and they pass it, some might see it as a blitz. I think I've got different definitions."

Flores then asked how the football-watching public defines a blitz. Told the generally accepted metric is any play with five or more pass rushers, he replied: "OK. So then we blitz a lot."

The Vikings have blitzed every quarterback they have faced, showing no deference even to Patrick Mahomes, the Chiefs' two-time league MVP who rarely faces extra pressure because defenses are afraid of how he might beat it. Against the 49ers, Flores will try to recreate the success he had in 2020, when the Dolphins forced three turnovers and Shanahan benched Jimmy Garoppolo in a 43-17 Miami victory.

Purdy has shown one of the league's quickest releases, though things could change if his best two catch-and-run weapons (Christian McCaffrey and Deebo Samuel) are both out because of injury. The Vikings could also try to exploit a San Francisco line that has shown weaknesses beyond Pro Bowl left tackle Trent Williams, who is listed as doubtful.

The Vikings will have to sustain their pressure rates without Davenport, though, while sifting through Shanahan's motions, devising ways to beat play-action passes and readying themselves for the punishing approach the 49ers have used for years.

"You look at blocks, they're blocking through the whistle, after the whistle," Hicks said. "Running backs are falling forward. Everybody is trying to be physical, trying to finish plays. They've been that way for years. When I was out in Arizona and playing them, you walked away from that game just a little more sore. It's just their personality. You've got to get your mind right."

The Vikings hope they have the antidote in a defense that seems to be ever-changing.

"We just want to throw different things at different angles at all times," Metellus said.