Who are Kevin O'Connell's Vikings? The big reveal is coming Sunday

The first pregame introduction of the Kevin O'Connell coaching era will take place inside U.S. Bank Stadium on Sunday.

The Vikings stadium operations staff should put away the pyrotechnics, turn down the insanely loud music and, instead, fire off plumes of either blue or pink smoke as players run onto the field.

It feels like we're invited to a gender reveal party.

Except this will be a football reveal party. One big mystery: these O'Connell-led Vikings.

Oh, sure, we know plenty about Justin Jefferson and Harrison Smith and Kirk Cousins and Adam Thielen and Dalvin Cook and Eric Kendricks and Danielle Hunter. But we have no concrete evidence for how O'Connell and his staff plan to employ them.

All we know for certain is that it will be different. How different? O'Connell kept that a closely guarded secret throughout the preseason.

The first-year head coach rested his starters almost exclusively in three preseason games. Most teams keep their game plans vanilla in preseason games for competitive reasons. O'Connell didn't even offer a taste of the vanilla.

O'Connell let his guard down Wednesday and gave the Green Bay Packers some deep intel on his team's best player, Jefferson.

"Justin is going to line up in a lot of places," O'Connell acknowledged. "That's no secret."

Everything else is TBD. Game 1 should come packaged with a giant bow.

Cook referred to the offensive coaching staff as "big brains" and said he's excited to see how he gets used in the new scheme, joking (allegedly) that he might be called upon to throw a pass.

"If I do throw a pass," he said, "it's going to be a check-down."

"I'll go for the big one," Cook amended.

That's the spirit. Might as well get weird because everything is so new and fresh and unknown.

Here's what we know or think we can expect: Jefferson will be superb, the defense will look different in a 3-4 alignment, fans will hold divided opinions on Cousins, and everybody will be mad about something at some point.

Here's what we don't know: A lot.

Start with O'Connell himself. How does he handle offensive play-calling duties? How does he manage a game, specifically two-minute situations? What will he do when it's fourth-and-2 from the opponent's 45-yard line when leading by a touchdown? How does he fare with challenges? All unknowns at this point.

The most fascinating unknown involves Cousins and whether O'Connell, a former NFL quarterback, can pull more out of him through either scheme or empowering his 34-year-old quarterback to take more risks. Cousins said Wednesday that he's not anticipating any mythical switch that gets flipped.

"I think I'll still play the position the way I've played it," he said.

The good news is that the Vikings' defense almost assuredly won't play the way it did last season. It's hard to fathom things being worse.

Ed Donatell's 3-4 scheme is a new toy that looks more imposing with Hunter back from injury to harass quarterbacks along with his tag-team partner and new best bud Za'Darius Smith.

The curiosity factor is higher for the defense than offense because the scheme is such a radical departure from Zimmer's defense, and there also are more new faces in personnel.

Sunday will provide more clarity about O'Connell's operation. His record also will no longer be 0-0.