At the end of Sammy Hagar’s set in Wolverhampton, something rather special happens.

Hagar brings Jason Bonham out for Led Zeppelin’s “Rock And Roll”, then, midway through, calls for Jayler singer James Bartholomew. Out he comes, trading vocals with Hagar while Bonham pounds away behind the kit.

For a young rock singer, surely that’s every fantasy made real.

A couple of hours earlier, Jayler had shown exactly why they belonged on this stage.

MV hasn’t seen them for a little while, and the improvements since Voices Unheard are obvious. Given how good they were to start with, that’s saying something.

“Down Below” carries the Zeppelin influence proudly, while Bartholomew straps on the guitar for the bluesier “No Woman”. “Riverboat Queen”, the first single from the album, grooves magnificently.

“Lovemaker” feels like Jayler acting out every rock ’n’ roll fantasy they’ve ever had, and Tyler Arrowsmith on guitar looks every inch a hero in waiting.

“Over The Mountain” is perhaps more personal but no less groovy. These songs could have emerged at any point since 1970 and belonged, which makes Jayler’s youth even more impressive.

They finish with the epic “The Rinsk”, as they do on the album, and it underlines both their confidence and ambition.

This was the first night of two major tours. By the time Jayler finish supporting Deep Purple this winter, expect a proper breakthrough.

Sammy Hagar has spent years living the high life in Mexico. He owns bars, has his own tequila and, when “Mas Tequila” is played tonight, the screens show footage from the Cabo Wabo Cantina and some of the many stars who have jammed there over the years.

Then again, you don’t get to do this for more than 50 years without making some kind of impression.

It is 31 years since MV last saw Hagar. Back then, Van Halen were opening for Bon Jovi at Wembley Stadium. To say it has been too long since he was on these shores barely covers it.

Perhaps that is why, from the second “There’s Only One Way To Rock” starts, the years simply melt away. Christ, what a way to begin.

“Top Of The World” follows and the feeling is almost overwhelming. My God, hearing these songs again.

There was a time around 1994 when songs like “Runaround” were my world. Three decades later, Hagar somehow appears to be exactly the same frontman: smiling, laughing and acting as though being onstage is the greatest thing anyone ever invented.

“Best Of Both Worlds” sounds colossal, and when you have Joe Satriani playing Eddie Van Halen’s parts you are not so much replacing the irreplaceable as finding a genius capable of making the music his own.

“Big Foot” dusts off the Chickenfoot catalogue. Fair enough, too, given that two of that band are standing onstage. Michael Anthony remains one of rock’s great bass players and backing vocalists, and there is an easy chemistry between the pair that no amount of time can diminish.

Then there is “Bad Motor Scooter”.

What a band Montrose were. The screens show Evel Knievel footage as that riff explodes from the stage. Fifty-three years after the song was released, it still sounds dangerous.

“5150” cannot be overlooked either. I can remember buying that record, and hearing its title track live all these years later is one of those moments where the past and present collide.

The same is true of “Love Walks In”. A proper ballad. The sort of song you taped off the radio as a kid. As Hagar stands above the stage on the riser, there is a sense of the scale of his career and the enormity of these songs.

Before “Cabo Wabo”, he mentions the football. Then we are transported to Mexico, where this whole other chapter of Hagar’s life exists.

“Mas Tequila” is pure celebration. Anthony plays bass as only he can, while Hagar hands tequila to the front row. Not drinking has seldom seemed such an inconvenient lifestyle choice.

“Here’s a song from ’92,” he says before “Why Can’t This Be Love”.

Then he pauses.

“I mean ’86.”

He laughs. It must be something to have had so many enormous songs that you forget when they came out. Anthony takes the second verse and the whole thing becomes a celebration of the bond these men have with the music and each other.

“Right Now” simply sounds enormous.

There is no other word for it.

Then Anthony takes the lead vocal on “Somebody Get Me A Doctor”, before Satriani gets his own showcase with “Satch Boogie”.

And what a joy it is to see Joe Satriani play guitar.

No gimmicks needed. No fuss. Just one of the finest players of his generation doing something that very few people on earth can do.

“Good Enough” begins with the trademark “Hello, baby!” and eventually turns into a loose jam while everyone sorts their drinks out. That might sound chaotic. Instead, it feels like you have been invited to watch the best house band in history messing around.

Nathan Mercado on keys and Kenny Aronoff on drums are vital to the whole thing, because this is not simply a nostalgia exercise. It is a proper band.

That is never clearer than on “Heavy Metal”. Forty-five years old and fresh as a daisy, it becomes another communal affair, with Anthony and Mercado adding vocals, while Hagar trades licks with Satriani.

This is a group that clearly enjoys each other’s company.

“I Can’t Drive 55” ends the main part of the set, with Hagar joking that he got the speed limit changed and Satriani playing guitar with his teeth.

Honestly, what else do you need?

Hagar claims they don’t do encores, but “Eagles Fly” follows. He calls it his favourite song he has ever written, and in this setting its simplicity is striking.

Then comes something even more emotional.

Before “Encore, Thank You, Goodnight!” there is a short film about a dream Hagar had about Eddie Van Halen. The song itself is a tribute to his friend, and when he sings, “thank you for the music, thank you for the songs”, it is impossible not to think about everything that has passed.

The people. The records. The gigs. The 31 years since Wembley.

At the start of the night, Hagar says they are going to try to please everyone and jokes that its impossible.

He’s not wrong  There are the fans who want Montrose. The solo years. Van Halen. Chickenfoot. There are people who have waited three decades for this music to return and others who might be hearing it live for the first time.

Somehow, though, Sammy Hagar and this magnificent band manage it.

This really was the best of all worlds.