But more on Def Leppard soon, because up first were 70s and 80s psychedelic folk rock balladeers Heart, led by Wilson sisters Ann and Nancy.
They started with a cover of Zeppelin's Rock'n'Roll, before the rugged folk whimsy of 77's Magic Man (with its pagan-like ritual mid-song breakdown), and the prog-meets-metal gallop and chug of Barracuda, which was dedicated to the All Blacks.
It was a howler of a song, with Ann Wilson's voice at its lethal and steely best, and one the boys in black should be warming up to on Sunday.
Heart, who also played their many epic and over-wrought ballads, including Alone, were an ideal warm-up act for Def Leppard.
Hard-strutting frontman Joe Elliott, guitarists Phil Collen and Vivian Campbell, one-armed drumming demon Rick Allen and glamour boy bass player Rick Savage know the score.
So they played all the big hits, and nothing but the hits, with Rocket a highlight thanks to Elliot's Gregorian chant-meets-hair metal vocal midway through.
But first up there's Undefeated, basically a homage to Def Leppard (and why not - it's been more than three decades and still counting).
And on the instrumental Switch 625, written by the band's late guitarist and bad boy Steve Clark, they ditched the hair bit and just played metal (albeit with a fantastical touch).
While Hysteria was a little dreary, with Elliot's muffled and coy mutterings, it was a solid day at the arena office for these 80s survivors.
And you can tell that Joe and his merry band of lads are still enjoying their job.