Vikings defensive lineman Harrison Phillips said the defense frustrated then-quarterback Kirk Cousins early during organized team activities (OTAs) with defensive coordinator Brian Flores in 2023.

It was supposed to be an easy day with both sides trading vanilla plays. Not much of the playbook had been installed yet, only a few months after Flores was hired.

Instead, Flores mixed in surprise exotic looks to mess with the offense, which didn't have answers.

Cousins wasn't the only one frustrated, Phillips said. He could tell the defense's dominance that day was getting to head coach Kevin O'Connell a bit, too.

O'Connell, Cousins and the offense had their own tricks dialed up the next day.

"It was a fun cat-and-mouse game for those first few weeks," Phillips said Wednesday.

Safety Camryn Bynum seemed to confirm the story with a laugh Thursday but claimed he didn't remember much.

"We pride ourselves on bringing a lot of mental warfare, as any defense would," Bynum said.

Cousins, who returns to U.S. Bank Stadium on Sunday with the Falcons, is coming off three straight performances even more frustrating than those early Vikings OTAs.

He's thrown zero touchdowns while racking up six interceptions, one away from tying his total through the first seven games of the season. He's been sacked seven times and has four fumbles, though none have been lost.

If Cousins is the "bounce-back type of guy" as Flores described him on Tuesday, Sunday's game is a prime time to show it.

"I'm expecting his best," Flores said. "The best version of Kirk. The best version of that offense. It's gonna be a major challenge for us, and we're gonna have to prepare the right way to have success against this group."

So how does a defense prepare for a quarterback it knows like the back of its hand? Is there a competitive advantage to knowing a quarterback so well?

Safety Josh Metellus said not generally. Even with seven seasons of tape on Chiefs quarterback Patrick Mahomes, he pointed out, defenses haven't found a way to consistently limit the three-time Super Bowl MVP.

With Cousins, though, there may be some edge.

"I would say the more competitive advantage is just him on himself," Metellus said. "That anxiety of having to walk into a place that you called home, being on the opposite side of our crowd and stuff like that."

Phillips and Bynum said they haven't gone back over any of Cousins' tape from the days they went against him in practice, sticking to his Falcons reel.

Phillips has seen differences in the Falcons' run game and pre-snap motions despite Atlanta offensive coordinator Zac Robinson coming from the same Sean McVay coaching tree as O'Connell. The Falcons play a pistol offense with Cousins, which isn't what the Vikings used.

There are in-depth conversations happening on both sides of this matchup, Flores said, using the knowledge from when his defense and Cousins shared the same practice field.

Flores is asking O'Connell about how Cousins will respond to "a list of things" his defense plans to throw at him. Cousins is likely telling his coaches which defensive matchups they can exploit with their crop of talent that includes running back Bijan Robinson and wide receivers Drake London and Darnell Mooney.

"We're gonna have to do a really great job from a disguise standpoint, from a crowd-noise standpoint … from a just fundamentals and communication standpoint," Flores said. "Because he can run his team into a call and out of a call or into another call with a couple hand signals. He'll go to the line and check the protection. He's that type of football mind."

What little Flores said about the game plan against Cousins sounds not unlike that first day of OTAs: Throw a lot of looks at him.

That slows a quarterback down, Metellus said, which is crucial for one as intelligent and experienced as Cousins. It gives pass rushers time to hit home.

But Sunday isn't just friendly practice competition. Cousins is trying to stop a midseason slump and pull the 6-6 Falcons back to a winning record. The 10-2 Vikings have a shot at clinching a playoff berth with a win.

Phillips said teammates have told him if he gets a hit on Cousins, he can't help him up.

Metellus is one of those teammates. He's gotten on defensive lineman Jerry Tillery for doing it before.

"We're at war," Metellus said. "Don't get me wrong — you can ask anybody — I'm a great sportsman. ... During the game, I'm not helping you up because that's gonna give you extra energy to do something to me and help us lose."

That's been a resounding theme of the week from Vikings defenders.

There's a respect for Cousins, and they'll be sure to greet him with smiles pregame and hugs after, but come game time, the competitiveness will take over.

At least for the most part. Phillips said he'll probably still extend an in-game hand anyway.

"I'll ask him how the kids are doing. Ask him how his place in Florida is," Phillips said. "I hope that he has a super-healthy game, and I hope that our fans welcome him in an appropriate way if his name gets announced or whatever.

"And, I hope that we win."

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