there is something wrong about this Ashes series, something nagging, unfamiliar. It is a bit like turning a corner and finding that somehow the landscape has shifted without any kind of warning.
Four years ago, going down to Adelaide was to run an Aussie gauntlet, one thrown down here in the big concrete stadium when the slaughter of England began with the clearest indication it would carry on all the way to the end of the road in Sydney.
It was intimidating, but it gave a wonderful edge and if the batting of Kevin Pietersen and Paul Collingwood had been built on more intelligently, if maybe Monty Panesar had been picked in the first rush of his optimism and talent, who knows? England might have found the means at least to make a fight of it.
Today going down to Adelaide is, almost weirdly, just another journey.
Something has changed apart from the fact that England plainly are bringing more nerve, more sheer competence to the challenge of hanging on to the Ashes. What it is, it becomes clearer the more you reflect on these last few days, is the Australians.
No one needs telling they are not nearly as good as when they had Matthew Hayden, Justin Langer, Adam Gilchrist, Shane Warne and Glenn McGrath – and you saw Warne sitting on his own on the Adelaide plane twirling a shiny Kookaburra as though he was casting another batch of new spells.
No, of course, you cannot replace such quality in a few seamless years, but maybe you can keep a certain way of thinking, the kind of intensity which may not grow on trees but has so long been the legacy of great Australian cricketers. You can keep a fire stoked. You can remember who you are supposed to be.
After England's Alastair Cook and Jonathan Trott built another record mountain of runs on the last day, Australia's captain, Ricky Ponting, rejected the claim that his team had for several days been using a body language featuring almost exclusively the word resignation. Where was the old gut-wrenching refusal to grant their opponents an inch, or a run, that wasn't hard-won? Where was the doomsday sledging?
Ponting said that, in his opinion, the body language had been pretty good most of the time but by mid-afternoon on Monday they were all looking up at the scoreboard and seeing the extent of the futility that faced them. "One wicket for more than 500 runs," he said, "is a pretty demanding score." He said it with a smile, but it was an extremely small one and tight at the corners.
Ponting did, after announcing that Doug Bollinger, who was controversially excluded from the first Test, and Ryan Harris would join the squad in Adelaide, concede that much of the Australian bowling was a cause for concern and would be reviewed thoroughly before the resumption of action on Friday morning.
Peter Siddle, the wood-chopping champion from Victoria, is presumably immune after his sensational hat-trick on the opening day, but long before Cook and Trott were called back to the dressing room Siddle's feat might have belonged to another age and another planet.
Certainly, the track had slowed beyond the imagination of most Australians, and offered little more encouragement to Jimmy Anderson, Stuart Broad, Graeme Swann and Steve Finn when they went through the formality of a late charge. However, it was as though Siddle, Ben Hilfenhaus and Mitchell Johnson had entered some unbreachable void.
It is Johnson who maybe suggests most strongly that something has indeed changed in the Australian cricket psyche.
Dramatically effective in the explosive bursts that have swelled his total of wickets beyond the mark set by the great Jeff Thomson at the same stage in their careers, Johnson lived through a nightmare here in Brisbane. He didn't get a wicket, he made a duck – barely a week after scoring a century and a five-for on behalf of Western Australia – and dropped Andrew Strauss when he was in full flow towards the century that would free him from the hard pressure that came with his third-ball dismissal in the first innings.
Australia's key man was near anonymous. He was also, at least on the outside, more passive than you imagine the likes of Thomson and McGrath while at their sleep.
Those who know Johnson best say he is a young man of great charm who just happens to earn around one and a half million dollars a year and long ago became an A-list celebrity – and that in his story we might just have seen an inkling why Australia may indeed be different now.
Also, why the fans who once identified so strongly, and so closely, with their heroes, are perhaps now at a greater distance than ever before, and certainly they left the stadium to the English yesterday – and had fallen away considerably on a fourth day that had started with such strong promise of another Australian win.
The worry, not just for the natives, is that something indeed may have snapped in one of the greatest sports traditions the world has ever seen. The old furies of Australian cricket were, after all, built on the assumption that there would always be another Warne or Ponting or McGrath impatient to make their way into the hearts of the nation.
There was not much evidence of such burgeoning authority and confidence these last few days. Maybe it is just a pause in the production line – and perhaps something will happen in Adelaide these next few days. Maybe the Australians will look a bit more like Australians. Maybe in some little town out in the bush the new Warne is working on a few spells.
If it is so, he needs to be doing it with some urgency. The danger is that when a certain magic disappears it is not so easy to retrieve. Australian cricket has lost one superb generation and, for the moment at least, it is not so easy to banish the fear it might just have been the last.