EAGAN, Minn. — The Vikings quest to plug the middle of the defensive line in 2020 will rely on versatility and a bit of variety.

Minnesota initially planned to replace mammoth nose tackle Linval Joseph with Michael Pierce, but the free agent opted-out because of medical concerns amid the COVID-19 pandemic.

There's no question that the position is important to Head Coach Mike Zimmer. When he was hired in 2014, one of the first free agents the Vikings signed was Joseph.

Joseph totaled 88 starts, 15 sacks, a glorious fumble return touchdown at Philadelphia and a pair of Pro Bowls. He is now with the Chargers.

The team also mined Shamar Stephen in the seventh round of the 2014 NFL Draft, and he spent much of his early career subbing for Joseph.

Stephen has started 35 of 67 games in five seasons with the Vikings, a run that was interrupted by one season (2018) with Seattle, where he opened 14 of 15 games with the Seahawks, focusing at nose.

Last season, Stephen did most of his work at the 3-technique with Joseph at nose.

Now, the Vikings have moved Stephen to nose and incorporated Jaleel Johnson at the 3-technique for most of the work with the first team.

Whatever is fine for Stephen — and Johnson, for that matter.

"I'm comfortable at both positions, 3 or nose," Stephen said. "I mean, I started out coming here at nose, so I just feel comfortable with both. And honestly, I'll play whatever position you want me to play."

Johnson, a fourth-round pick in 2017, said he appreciates the opportunity to focus mainly on the 3-technique, but he understands the need to do "some nose tackle stuff throughout the year and training camp."

The nose and the 3-technique both fall under the umbrella of defensive tackles, but they have different responsibilities and approaches in the Vikings system.

Vikings Co-Defensive Coordinator/Defensive Line Coach Andre Patterson said Johnson "looked so much more comfortable" at both defensive tackle spots in 2019, his third pro season.

"The style of play changes at each position," Patterson said. "Last year, [Johnson] could go into 3-technique and be productive, then he could go into nose and change his stance and be productive at that, too.

"His confidence level went through the roof," Patterson added. "He finally understood he was a good football player within our scheme. Now, I'm hoping that confidence level takes over again this year, and you see his game rise to a whole another level because of that."

Patterson said Iowa's approach at the defensive tackle spots was assigning left and right defensive tackles that adjusted assignments based on the look by the offense.

"What I mean by that is if he was the right defensive tackle and the tight end came out to the right, he was a 3-technique," Patterson said. "If the tight end came out to the left, he was a nose. So, it wasn't like he had never had the experience of playing nose before."

The stance by Hawkeyes players didn't change, but it does with the Vikings, depending on whether a player is at nose or 3.

"The way we played it at Iowa, being a 3-technique, we still had our hand down next to the ball, tilted forward and getting off the ball a little bit. It was the same thing at nose tackle, too. I played that for four or five years," Johnson said. "Then coming here to Minnesota, our nose tackles are required to have a balanced stance and not really coming off the ball. It takes some adjustments, it takes a while to really adjust to that, but once you get in the habit of doing it every single day, it's like second nature now."

Said Patterson: "Most people … stay in the same stance and stay with the same technique. But for us, it's different, so when the young guys come in here, that's the thing where it takes time for them to figure out."

Nose tackles often gobble up double teams by an opponent's guard and center, leaving a 1-on-1 with a guard for the 3-technique. There are other differences, as well.

"Once you're out there [at 3-technique] and you have a little bit more space, you're able to see things a lot quicker and react a lot faster as opposed to being the middle, where everything is coming full speed and centers and guards are whamming you every single play," Johnson said. "You have some space to really move around and play free."

Both spots involve a great deal of dirty work that often goes unnoticed by many but is valued by coaches and teammates (Lindsey Young will have more on Stephen's value on Aug. 23).

The Vikings are young and varied at defensive tackle behind Stephen (listed at 6-foot-5 and 309 pounds) and Johnson (6-3, 309). The body types of other DTs on the roster range from Hercules Mata'afa (6-2, 254 pounds), James Lynch (6-4, 289), David Moa (6-3, 296) and Armon Watts (6-5, 295).

Patterson said the Vikings will cross-train all of the defensive tackles, making use of versatility and variety.

Johnson credited Patterson for helping players feel comfortable within the Vikings system.

"Just going out and working hard every single day in practice and just working techniques, whether it be in offseason, OTAs … when that opportunity arises, for guys to step in, and it's not like a deer in the headlights," Johnson said. "It's almost like, I wouldn't say stepping into a role that you've been given, but it's something that we worked hard for, we earned that position, and the grind doesn't stop. It's really just a matter of keep going forward."