Shamar Stephen is called the "Big Fundamental" by his Vikings position coach, co-defensive coordinator Andre Patterson, which is a nod to former San Antonio Spurs superstar Tim Duncan and Stephen's quiet proficiency at defensive tackle.

So, there is little surprise about how the Vikings' plans have unfolded to replace nose tackle Michael Pierce, the prized free-agent signing who opted out of the season because of COVID-19 concerns. Stephen has been moved to nose tackle, and Jaleel Johnson is expected to replace him at defensive tackle.

Stephen, a 2014 seventh-round pick, moves back to where he started his NFL career, and where holding up multiple 300-pound offensive linemen can be a thankless job.

"If my job is to hold up a block or choke off a block, that's what I'm gonna do," Stephen said. "You see the snapper doesn't get any credit, but he's the most important thing for the ball to get kicked, right?"

To keep the field clear in front of All-Pro linebacker Eric Kendricks, head coach Mike Zimmer chose the line's most experienced player in Stephen, who is tied with defensive end Danielle Hunter for most years in the system.

Stephen was re-signed in 2019 to play defensive tackle next to Linval Joseph, but replacing Joseph is a better fit, according to Zimmer. The Vikings originally drafted Stephen to compete as Joseph's backup.

"Shamar has basically been a nose tackle most of his career," Zimmer said. "That will be a better position for him, anyway."

Replacing Joseph, a two-time Pro Bowl player who left for the Chargers in free agency, is easier said than done. Nose tackle is high on the priority list for Zimmer, who made Joseph the Vikings' first big addition upon being named head coach in 2014 and, to replace Joseph, signed Pierce to a big deal.

Stephen may not be in the spotlight often, but he's a figurative and literal center of the defense.

"We're at the start of the ball. So, if anything happens to the nose, it's down the middle of the field to the end zone," Stephen said. "We all play a piece in the puzzle, and if we all do our job, we'll be able to have a great defense this year."

Stephen, in his seventh season, is also the elder statesman of Vikings defensive tackles. The rest have a combined five NFL starts, including four from presumptive starter Johnson. One of Johnson's starts — a Nov. 10 victory at Dallas — gives coaches confidence after a Joseph-less defense surrendered just 2.4 yards per carry on Ezekiel Elliott's 20 runs.

"We played that game with Shamar Stephen and Armon Watts and Jaleel Johnson," Patterson said. "They played great that night. We have great competition in that room at that position, and I think we're going to be just fine."

The understated Stephen, in some ways, is an ideal backup plan for the Vikings. Setting up others for success is the job of a Vikings nose tackle, as Stephen and Joseph were often credited by coaches — and by Kendricks — for assisting the linebacker's All-Pro 2019 season.

While other NFL defensive systems may turn loose defensive tackles to blow up plays in the backfield, the Vikings ask both defensive tackles — especially the nose — to clog the line and prevent offensive linemen from blocking linebackers. Not coincidentally, Stephen's most frequent penalty is defensive holding.

But Stephen won't necessarily be noticed if he is doing his job properly this season.

"Their number one job in their life is to not let anybody touch Eric," Patterson said. "People write stuff about Shamar Stephen, and I get it because everybody just looks at stats. But if you watch film and you ask Eric Kendricks if he had to pick anybody to go to the game with that he'd make sure that guy was there, I guarantee he'd tell you it's 93."