Grace Cummings is sadly sick tonight and unable to open the show. Instead we’re treated to a wildly different start to proceedings as the pub-thrash maniacs C.O.F.F.I.N. (also Australian) are somehow on hand to fill in. They manage to get a solid pit going within ten minutes and their frontman/drummer Ben Portnoy is always ready to keep things moving. He’s a whirlwind of a presence; beyond clattering the skins he’s swigging whiskey, barking and howling, falling over, giving a beautifully impassioned speech about resisting genocide (informed by the Aboriginal experience in Aus) and ends it all with a solid uppercut to his cymbal. Hard to imagine we’d be in this position following a set from Grace Cummings, and likely a few people wouldn’t have been smacked in the head by the Aussie Rules Football that was punted into the audience half way through.

There aren’t many young, contemporary acts that inspire fans to follow them round like Deadheads (Gizzheads has been attempted, to mixed reaction). But King Gizzard are basically the hard rock jam band at this point, and from their commitment to the art of rocking the fuck out it’s easy to see why the dedicated few want to see every show they can.

They open with ‘Magma’ which extends to a good ten minutes, demonstrating their proclivity to stretch a song well past its natural limits in service of the improvisatory muse. But the pits really get going with The Lord Of Lightning and from there it’s wall-to-wall headbanging and crowdsurfing for a good twenty minutes as we’re treated to a medley from the garagey, decade-old I’m in Your Mind Fuzz.

Around the midway point the band get into their bluesy mode, with Ambrose Kenny-Smith delivering some skronking harmonica (as he did earlier with C.O.F.F.I.N also) while the band get their choogle on. There’s a few moments for a breather here which is needed given the relentless pace, with comparatively lighter tunes like Gaia and The Bitter Boogie.

Stu McKenzie a relentless ball of energy all night; yucking it up in a kilt of his family tartan (he hasn’t shut up about it all day, according to Joey Walker), harvesting feedback like nobody’s business, stomping the shit out of effects pedal and following in the powerful Australian rock lineage of Angus Young with a few punky duckwalks.

The heavier material returns as we enter the home straight and Ben Portnoy of C.O.F.F.I.N helps out with a monstrous version of Rattlesnake that also incorporates Billabong Valley, Oddlife and Boogieman Sam. Faces are melted, brains are fried (the accompanying visuals reinforce the psychedelic whirlwind on display) and no-one leaving the sold out Usher Hall can be in any doubt about the earth-shaking bona fides of these most raucous of rockers.