Superstar receiver Justin Jefferson has returned from his offseason attending the Met Gala and F1 races to participate in a voluntary portion of Vikings spring practices that some stars might miss for extra vacation.

But Jefferson was in attendance Wednesday and has been for a couple of weeks, according to coach Kevin O'Connell. The Vikings receiver is participating during the first week of full-team sessions (or organized team activities), which he missed last year amid contract negotiations that eventually resulted in a $35 million annual pact.

There wasn't a reason to doubt Jefferson's commitment, but his presence suggests he's well aware that his bond with new Vikings quarterback J.J. McCarthy, last year's 10th overall draft pick, is a key in their path forward.

After a roughly 110-minute practice Wednesday, McCarthy met with local reporters and said he's spending a "good amount" of time with Jefferson on and off the field. They sat courtside at the Timberwolves' May 14 playoff win over the Golden State Warriors.

"It's been extremely huge," McCarthy said. "He's a tremendous talent, a tremendous leader, but his leadership really shows up when he's here. And just being able to get that chemistry building on and off the field has been invaluable."

There are limits to their team-building at this point — no pads or live contact — but Wednesday's session was plenty spirited as McCarthy went through his second of what can be 13 practices before training camp.

Don't read too much into it, O'Connell warned reporters.

"As an ultimate reminder, it is the learning and teaching phase of the offseason program," O'Connell said. "So, getting out in front of any rep questions, competition questions, tracking of completions and/or handoffs, I'll go ahead and allow the time of the year to speak for itself."

McCarthy said: "There's a lot of above-the-neck capacity today that we were just stressing. It's just so much fun out there to be able to hit some of those play calls and hit the reads … then there's some where you miss a certain part of the cadence, but at the end of the day, it's all learning."

At risk of providing too much to read into, here's a look at McCarthy's day:

Rainy skies push over 80 players into the team's fieldhouse at TCO Performance Center, where McCarthy warms up for nearly 15 minutes alongside half of the team occupying one end zone.

Following a nearly 15-minute warmup period, quarterbacks and centers rep snaps. McCarthy's relationship with new center Ryan Kelly, a former Colts Pro Bowl player, is another critical union for the Vikings. McCarthy said they've twice met together with offensive line coach Chris Kuper away from the field. They need to be aligned in pass protection calls and cadences.

"Base stuff and just being on the same page with that," McCarthy said. "It's a continued process. That relationship is going to grow."

McCarthy, who missed his rookie season because of an Aug. 10 torn meniscus, said he's just happy to be playing again.

"It feels amazing," McCarthy said. "When you get it taken away from you, you'd take every chance you get to get back out here and really appreciate it and get the most out of it."

For at least Wednesday, the Vikings' pecking order at quarterback went McCarthy, Sam Howell, Brett Rypien and Max Brosmer. That's how they consistently aligned, including during the practice's fourth period, which focused on under-center and shotgun handoffs.

The Vikings' many former quarterbacks — coordinator Wes Phillips, position coach Josh McCown, assistant Jordan Traylor — huddled with run game coordinator Curtis Modkins and offered pointers to McCarthy and others as they worked through timing and footwork.

O'Connell, the head former quarterback, then grabbed all four quarterbacks' attention for a couple of minutes of instruction. Last season, O'Connell met with McCarthy every week to discuss the game plan. He said he's told McCown to have a "no stone unturned" approach with the 22-year-old quarterback and not to assume he recalls everything.

"I've been really surprised by some of the things that he does know," O'Connell said. "You're like, 'Man, we covered that in a 10-minute burst in Week 11 last year; how do you remember that?' And then there's some other things where you're like, 'Oh, I assumed he knew that.'"

Roughly 51 minutes into practice, McCarthy lines up with part of the offense for the first of two seven-on-seven passing drills. He completes seven of 10 passes, but not the first throw to Jefferson over the middle. Cornerback Byron Murphy Jr. jumps the crossing route and linebacker Ivan Pace Jr. catches the deflection — the first jab by a secondary that batted and ripped away passes. Cornerback Dwight McGlothern knocked away another later in the session.

"Everyone wants to be perfect, especially at the quarterback position," McCarthy said. "But the more you try to be perfect, it's going to kill you more than your imperfections will. I just feel like being able to accept in these learning, teaching phases that it's OK to learn and fail and try things and take risks."

"Most of the risk is anticipatory throws," McCarthy said, "trying to fit it into a tight spot and try little things with my footwork and my eyes."

O'Connell clarified what he's looking for from McCarthy in those moments.

"You can really get a feel for, 'Is a guy reading with his feet?'" he said. "'Is he taking the right drop? Is his base and body and balance positioned to the throws and sequence of the drop in the proper place? And did he make the throw? And then was it accurate?' And then you can kind of coach backwards from the ending of the play."

During the first of two 11-on-11 periods, McCarthy operates the huddle with O'Connell calling the play into his in-helmet speaker. He completes passes to running back Aaron Jones, Jefferson and receiver Jalen Nailor, among others, during a 15-minute session against a half-speed defensive front that isn't allowed to hit anyone. McCarthy's longest throw lands complete to Jefferson in the back of the end zone about 50 yards away.

"How many situations can [O'Connell] put me in where I'm able to almost be on my own a little bit," McCarthy said, "and now we come back together, regroup and talk through it, and that's why this learning and teaching phase is so huge … where we can be uncomfortable and there's no consequences."

McCarthy ends the day with a quick hurry-up drill: a couple of tosses against a half-speed defense and a spike to stop the clock.

He relived all that in much more detail on his own Wednesday evening.

"During treatment, I watch the film once, a quick buzz through it," McCarthy said. "Really eye-candy stuff; how did it look from a base perspective? And then I dive deeper into it that night and just go over each play and really all the intricacies of what I saw, what I didn't see and why that was the case.

"And then the next day, we're in here dissecting it."