At set's end, a saxophonist dressed as a glittery wizard bounds on stage, blowing a wild solo. He begins to duel frontman Billie Joe Armstrong, who's playing a kazoo, before bleating Yakkity-Sax and sending Green Day galloping about the stage like cloned Benny Hills. Truly, the Sex Pistols were never like this.

But then Green Day long ago ditched any semblance of punk-rock "cred", a move that's served them well. The Berkeley trio slam-danced into the zeitgeist with the bratty pop-thrash of their masturbation-obsessed third album, 1994's Dookie – though such teenage kicks, while hard to beat, were also tricky to keep fresh. Subsequent LPs disappointed, until 2004's American Idiot – a punk-rock opera that's now a successful Broadway show and soon-to-be Hollywood movie – returned them to club multi-platinum.

It's the songs from these twin peaks of their discography that are received most feverishly tonight: the blunt, dynamic Longview (a Pictures of Lily for the Warped Tour generation), the irresistibly catchy power-chords of American Idiot. New material debuted tonight, from forthcoming album trilogy ¡Uno!, ¡Dos!, ¡Tre!, is similarly immediate: Stop When the Red Lights Flash is bold and brash, while new single Oh Love boasts a faux-Celtic chorus that makes Mull of Kintyre sound like Metal Machine Music. Green Day don't really do subtlety; they're like being hit by a clown-car stuffed with hooks, and harmonies, and also balloons.

Armstrong barely pauses for a breath throughout the two-hour set, a hyperactive Looney Tunes imp leaping off the monitors into scissor kicks, drenching the front row with a water pistol, and shooting toilet roll into the balconies. He invites a kid on stage to play guitar – a trick he's done at every Green Day show I've seen – but he takes such pleasure in the skit that it feels spontaneous. In another life he'd have made a fine children's TV presenter, though, as Keystone Cop ringleader of this tune-studded circus, he's found his perfect outlet as an entertainer.