What will the Vikings do if Stephon Gilmore is sidelined? Trust in newcomer Fabian Moreau.

Cornerback Stephon Gilmore is one of the players many assume the Vikings can’t afford to lose for any extended period of time and still win games.

Yet defensive coordinator Brian Flores didn’t budge when Gilmore strained his hamstring in the first half of Sunday’s 23-22 win over the Arizona Cardinals.

The next cornerback on the depth chart, Fabian Moreau, is a seasoned, 30-year-old veteran. But he had played just one defensive snap all season before Gilmore’s injury.

Flores stuck with a man-to-man heavy game plan that eschewed the Vikings’ typical zones for a physical, tiring brand of coverage that asked their defensive backs to sprint with receivers. The plan made Moreau, who was targeted on a team-high 21% of his coverage snaps, an easier mark for Cardinals quarterback Kyler Murray.

“I hadn’t played since the preseason,” Moreau said Wednesday. “So, coming in and doing my assignment, I feel I played well. Of course, there’s a couple plays I’d like back like any game.”

But Moreau graded out well by Vikings coaches who saw more than the two pass interference penalties and a 15-yard touchdown catch allowed to Cardinals receiver Marvin Harrison Jr.

“Fabian played really well,” Flores said. “Thought the coverage was tight. They made a couple throws. He had a couple interference penalties, which you never want those, but I thought overall when you really watch it, snap after snap, the coverage was tight.”

Flores might need Moreau again on Sunday against the Atlanta Falcons — or for however long Gilmore is sidelined by a hamstring injury that can be a tricky recovery. Coach Kevin O’Connell said the Vikings will be “smart” with Gilmore, the 34-year-old veteran who did not practice Wednesday. Gilmore has played 85% of defensive snaps while starting all 12 games since signing in August.

“We avoided a serious longer-term injury,” O’Connell said. “At the same time, we’re into December now, and he’s given us a lot of great snaps. I feel really good about what Fabian was able to come in and do as well. We’re going to make sure that we’re smart with him, but by no means hold him back if he’s ready to go.”

If Gilmore can’t play, the Vikings will lean more on cornerback Shaq Griffin, who had the game-sealing interception against Arizona, in a pairing with Byron Murphy Jr. But the Vikings often deploy five- and six-defensive back packages that would likely see Moreau on the field against Falcons quarterback Kirk Cousins.

For depth, the Vikings signed former Cowboys second-round pick Kelvin Joseph, a fourth-year corner, to the practice squad on Wednesday. The Vikings also have rookie Dwight McGlothern, who has yet to make his NFL debut, and cornerback Nahshon Wright.

Moreau, 30, is by far the most experienced option.

He has amassed 58 NFL starts for five different organizations. He started for the New York Giants during the Vikings’ 2022 playoff loss at U.S. Bank Stadium, playing nearly every snap opposite Giants cornerback Adoree’ Jackson.

That playoff game was brought up jokingly when Moreau agreed to sign with the Vikings on July 31. But Moreau knew O’Connell before that game. They spent two years together in Washington, where Moreau was drafted in the third round in 2017 out of UCLA. Moreau said O’Connell is the reason he agreed to come to Minnesota in the first place.

“We just were always cool with each other,” Moreau said. “He’d always bounce a lot of questions off of me back then. So, when he called, I already knew I wanted to play for him.”

Moreau’s mind has impressed Flores, too.

“If he wants to coach down the road, he can certainly do that,” Flores said. “He’s very smart, understands the game … I feel like with the attrition in this league, you knew at some point we were going to need him, and he was ready to go.”

A subtle pre-snap movement illustrated Moreau’s readiness. Before he was flagged for being too tight in coverage on Cardinals receiver Greg Dortch, Moreau and Murphy quickly switched man-to-man assignments before the third-down snap in an effort to throw off Murray. It’s a simple adjustment but one built into a secondary that Moreau hadn’t yet played with in a game.

“It’s something that they do,” Moreau said, “and for me, I gotta know when I’m in there that I gotta do the same.”

Sticking with the man-to-man game plan against Arizona said something to Moreau’s teammates as well.

“That speaks to Fab and the confidence that we’re not going to get off the game plan because of injuries,” safety Harrison Smith said. “We have confidence in whoever steps up.”

The late picks by Murphy and Griffin marked the Vikings’ 13th and 14th takeaways in the fourth quarter this season, the most in the NFL. Only one other defense – the Steelers (12) – has reached double-digit takeaways in closing time, according to Pro Football Reference.

“Small details in the clutch,” safety Camryn Bynum said. “We ran man-to-man and we were able to make the plays. It was fun to mix things up and really go mano-a-mano.”

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