How will losses in secondary affect Vikings' defensive plans?

EAGAN, Minn. -- Veteran cornerback Duke Shelley signed with the Minnesota Vikings on July 23. Two days later, he was working with the first-team nickel defense.

Fellow cornerback Fabian Moreau followed an even quicker ascent. He signed on July 31 and was getting reps with the starting defense in his first practice.

Largely hidden behind the Vikings' quarterback drama has been an unusual level of roster manipulation at cornerback, a position it hoped would spearhead a schematic shift in 2024.

The Vikings lost cornerback Mekhi Blackmon to a torn ACL on the first day of training camp after already experiencing the tragic death of promising rookie Khyree Jackson on July 6. On the second day of camp, veteran starter Shaquill Griffin slipped while returning an interception and injured his hamstring. He has not practiced since, and while the injury is not expected to affect his regular-season availability, it was a reminder that other injuries have limited Griffin to one full NFL season since his arrival in 2017.

And so the Vikings' personnel and coaching staffs have scrambled to fill the gaps. In addition to signing Shelley and Moreau, they have also inked veteran Cobi Francis , acquired safety/cornerback Bobby McCain ,  given undrafted rookie Dwight McGlothern a run with the second team and moved safety Jay Ward -- a 2023 fourth-round draft pick -- from safety to cornerback. Meanwhile, 2023 starter Akayleb Evans , who opened camp as a reserve after being benched twice last season, has been a fixture with the first-team defense alongside Byron Murphy Jr .

"We're going to need him," defensive coordinator Brian Flores said of Evans.

The flurry of acquisitions could continue through the summer, as some more prominent veteran free agents, such as two-time All-Pro Stephon Gilmore , remain available. Coach Kevin O'Connell has indicated the position will continue to be evaluated.

"At the very least, you feel good about the numbers to have competitive practices and not tax those guys as they're all competing," he said. "It's a fluid thing. As always, we're constantly evaluating types of players that could be available to come in and provide a certain skill set or even just looking at what the final roster construction might look like -- where we may be able to improve in any area of our team with potential free agents that are still out there. But I do feel good about the room."

The personnel upheaval has coincided with Flores' plan to rebalance the Vikings' splits between zone and man coverage this summer. Long associated with heavy doses of man coverage behind his blitzing scheme, Flores deployed zone defense on 68.3% of the Vikings' snaps last season. That was the fourth-highest rate in the NFL , according to ESPN Stats & Information. The surprise shift helped the team lead the NFL in defensive efficiency between Weeks 4 and 14, but injuries and adjustments from opponents contributed to a late dip and a four-game losing streak to finish the season.

Flores' rate of man coverage has dropped in each of his five seasons as a defensive playcaller, beginning in 2018 with the New England Patriots and continuing during his tenure as the Miami Dolphins ' head coach from 2019 to 2021, but last year's splits proved unsustainable over a full season.

"Every year is different," he said. "I think you've got to reinvent yourself every year. And if you do the same thing every year, in this league the coaches are so good and the players are so good that they'll catch up to you -- especially if they know exactly what [coverage] you're going to be in. There is a concept or a run or a screen, or some offensive concept, that beats every defense. So if they know what you're in and they call it and they dial it up, they got you. I think you want to be in as many different structures and coverages as you can just to keep the offenses guessing to a degree.

"But at the end of the day in those critical downs you have to have the ability to play man-to-man coverage, and I think we'll try to do that a little bit more this year."

The question remains whether Flores can.

The Vikings devoted substantial resources to upgrading their defensive personnel this spring, signing three linebackers -- Jonathan Greenard , Andrew Van Ginkel and Blake Cashman -- while also using seven draft picks to maneuver for and select edge rusher Dallas Turner with the No. 17 overall pick. But other than signing Griffin to a one-year deal worth $4.55 million and drafting Jackson in the fourth round (No. 108 overall), they left their secondary largely untouched.

It's no secret that man coverage requires a level of skill and talent that isn't likely to be found on the free agent market during the first week of training camp. The Vikings' focus through the first two weeks was simply having enough cornerbacks to practice and give their offense credible defensive looks. Whether Flores can coax more varied coverages from this group is a question that simply can't be settled at the moment, even if it's typically the time when NFL teams test and adjust their offseason plans.

"A lot of people went down, and a lot of different guys are being mixed in," safety Cam Bynum said. "But everybody is capable, and I think it's been fun to just learn with different guys now. People have been walking straight in here like they've been here for a while, but it's been cool."