From the sublime to the catastrophic, Jay Weatherill spent much of yesterday basking in the political glow of Adelaide Oval’s successful Ashes showcase, yet ended the evening firing off a desperate missive to the PM as the Holden saga reportedly moved towards a bitter denouement.

If the second test is highlighting four Adelaide seasons in as many days, it’s also serving as a backdrop to a swiftly shifting political climate, one that encapsulates this Labor Government’s trials and tribulations. Just when it seems the tide is turning in its favour, another squall sends it again spinning hopelessly off course.

Holden’s reported exit is a massive blow, of course, but perhaps the political shrapnel will ricochet in the Liberals’ direction too. And, indeed, the exact state of play remains murky, indistinct. Rumours from “senior Federal Liberals” that a decision has been made as yet remain just that.

But it’s certainly crashed what was looming as Labor’s most festive few days in many a month. The feelgood factor surrounding the Oval’s (thus far) successful international showcase, with cricketing royalty and pint-pulling punters alike awed by the stadium’s transformation, heralded an almost tangible shift in the political zeitgeist. The Liberals, poised daily to pillory some aspect of the construction, prudently opted to lay low instead, rather than risk being the curmudgeon at the back of the room whose incessant grumbles start to kill the buzz for everyone else.

Labor figures, from Foley and Conlon to Koutsantonis and Weatherill have long claimed the Oval would be a “game-changer” for Adelaide. It certainly appears to be one for the electoral contest, reframing it amid a long-lost sense of state pride and optimism. Of course, with the inevitability of Murphy’s Law, a Holden crisis will quickly dispel the feelgood vibe.

Not that the Libs will have much capacity to capitalise: they haven’t, after all, posited much in the way of a solution, or even an opinion about the auto-maker’s worth. Rather, they want to see the empirical evidence. They need to be convinced.

It’s the same basic stalling tactic they’ve employed for two years now, typified by former leader Isobel Redmond in a speech to the Liberal AGM in August 2012: “We won’t have any real indication (about the true shape of the budget) until the mid-year budget review in December next year.”

She long insisted the Opposition was unlikely to reveal any big-spending policies until this magical date, an argument her successor seized upon with gusto.

“We’re looking forward to receiving the mid-year budget review and then we’ll announce to the people of South Australia what our plan is to return the budget to surplus,” Steven Marshall said in October. Of course, after the mid-year budget review was unexpectedly released this week, he declared he’d instead “be releasing our final financial document in the lead-up to the next election as per every other election in the history of this state”.

Mind you, as economic documents go, the MYBR was a particularly political one.

It was always likely the federal result would play some role in dictating the terms of the March state election; it was only ever a matter of degree.

As the Liberals pointedly observed, the past three pre-election budget statements have been dropped as late as January 28 in 2010, January 25 in 2006 and February 2 in 2002. Last year’s was on December 20. And they’re rarely, if ever, announced with no word of warning. This wasn’t your standard budget briefing. This was a gauntlet thrown down to the Opposition. This was a shot across the bows.

Yes, that’s a couple of inconsistent metaphors, but entirely consistent with the muddle of clichéd hyperbole that has surrounded this otherwise beige economic statement.

No sooner had the MYBR landed, the Liberals issued a statement decrying Weatherill’s “dangerous jobs crisis”. Even if you allow the fairly hysterical term “crisis” to describe our persistently lagging unemployment rate, surely “dangerous” is still a stretch. Unfortunate, perhaps. Alarming even. But dangerous?

Even if they’ve been a little lax on the policy detail, the Libs have been busy assembling a veritable army of snappy adjectives. It’s not just any carparking tax, it’s a Toxic Carparking Tax. It’s not your common-or-garden jobs crisis, it’s a Dangerous Jobs Crisis, a lurking monster of unemployment waiting to pounce when we least suspect it.

But the unusual timing of Weatherill’s first, and perhaps last, mid-year budget review as Treasurer was designed with only one intent: to flush out the Opposition; to show the Liberals up, by removing the economic caveat behind which they’ve successfully hidden for the past two years. And as a blatantly political foray, it was moderately successful, forcing the awkward admission that the Libs won’t be detailing any costings or cuts until well into the campaign proper. It won’t come to much, of course; the budget statement itself was effectively steady-as-she-goes; a marginally greater deficit, a marginally reduced debt. Enough for each side to claim the economy is either on or off track, as their respective scripts dictate.

And the gambit might have slightly unsettled the Libs, but not enough to put a dent in their campaign strategy. It was an insider’s victory, like having a good day in Question Time. It’s unlikely to swing any votes, not yet anyway.

And it smacks of more than a little hypocrisy, since Weatherill himself admits there are policies still to be announced that are not contained or costed in the MYBR. Like the Libs, Labor is keeping much of its powder dry (the good stuff as well as the bad) until the campaign proper.

But it has, at least, ditched its desultory, meandering bewilderment of recent months, galvanised by a Stones and Ashes hysteria, and perhaps by the scent of battle; girded for one final assault, even if it turns out to be a kamikaze one.

It’s unclear how much of this can be attributed to Weatherill’s leadership, but certainly the post-poll shenanigans on the Commonwealth front might have given Labor some cause for optimism. Tony Abbott’s administration has gone from a low-key start to a decidedly lacklustre one. Key South Australian Liberals have found it hard to tone down their sneering triumphalism, like children in the afterglow of a schoolyard scrap, and Christopher Pyne’s ubiquitous presence in the Abbott administration’s first major policy backflip (over education funding, in case you missed it) probably hasn’t helped enhance the Liberal brand locally.

It was always likely the federal result would play some role in dictating the terms of the March state election; it was only ever a matter of degree. Certainly, many Coalition voters only did so for want of a better alternative; indeed, there have been fewer less emphatic campaign slogans than the Liberal mailout that simply read: “Labor doesn’t deserve your vote.”

But Weatherill has been too easily allowed to paint himself as the mainland’s last bastion against Coalition stinginess, a de facto leader of the Opposition, standing up to “Abbottism”, and painting the enigmatic SA Liberal Leader as the son and heir of the PM’s economic rationalist tradition.

And that, rather than inelegant political surprises and economic booby-traps, will be what resonates on the campaign trail. That will insulate him, too, to some degree from the Holden fallout, if fallout there must be. He can respond to his critics as McMurphy responds in One Flew Over the Cuckoo’s Nest, after his aborted effort to escape the asylum: “Well, I tried, didn’t I, goddammit? At least I did that!”

Like Adelaide Oval, the federal election was indeed a political game-changer. The danger for Steven Marshall is that, while he persists in presenting a blank canvas, he allows Labor to fill the empty space with its Machiavellian art.

Tom Richardson is InDaily’s political commentator and Channel Nine’s state political reporter.