England's top-scorer James Vince had nominated the opening hour of day two as the window that might determine the outcome of the first Magellan Ashes Test, but it was a two-hour stretch immediately after lunch that may yet prove pivotal.
Having wrested the momentum of a grafting game by mopping up England's six remaining wickets with unforeseen haste in 15 overs prior to lunch, Australia handed it obligingly back to their rivals with a top-order batting effort that veered dangerously close to full-scale calamity.
In response to England's patient 302, Australia found themselves staring over the precipice in the first over after tea when Peter Handscomb's dismissal left them wobbling at 4-76. With the maligned Shaun Marsh and recalled keeper Tim Paine the only recognised batting talents available to stay with typically resolute skipper Steve Smith before the bowling brigade would be called upon.
However, against the backdrop of Glenn Maxwell's opportune if not quite timely double-hundred in the JLT Sheffield Shield, Marsh brought the experience and resilience that were cited as reasons for his recall and forged a vital stand with Smith.
At stumps of a Test match upon which neither team has been able to wrest a firm grip, Australia stood slightly more steadily but still in some discomfort at 4-165 with Smith unbeaten on 64 and Marsh 44 not out.
A not dissimilar position to England's 24 hours earlier, when Joe Root's team had battled to reach 4-196 on day one against an equally disciplined and dogged bowling effort on a pitch that has yet to allow for any batter to feel fully at ease.
Although the pitch could hardly be blamed for the early troubles Australia faced, with only David Warner – who tried to whip a delivery that held on the surface and accordingly punched a sharp catch to a fielder strategically placed at short mid-wicket – able to mount a case that he was undone by conditions.
Certainly Usman Khawaja's removal for 11 to just the second delivery of spin that he faced brought to mind his recent struggles against the turning ball in Sri Lanka and Bangladesh, travails that brought about his axing from the Test team on both occasions.
The fact that England captain Root threw the ball to his spinner Moeen Ali shortly after Khawaja went to the wicket in the fourth over indicated that news of the left-hander's issues against the turning ball have travelled beyond the subcontinent.
And while it's unlikely that pitches for the remainder of the Ashes summer will exhibit the grip and turn of the Gabba on the first two days, the fact that Khawaja again fell to a ball that snuck past the inside edge of his bat and into his pad in line with the stumps will ensure he faces a trial by spin early in most of his subsequent knocks.
Khawaja was called to the action early after Cameron Bancroft, in his maiden Test innings, recorded his first failure of a productive month when he nicked off to the immaculate length bowled by Stuart Broad, a fate that has befallen so many more-credentialed Australia Test batters in recent years.
Presented with the choice by his vastly more experienced opening partner Warner as to whether he would prefer to face the innings' first delivery or not, Bancroft duly faced up and recorded his first Test runs a few balls later.
But he was on his way before the shine was dulled from the ball, as the fears that Australia's top order might be exposed by Broad and his veteran ally James Anderson were instantly realised.
When Warner departed, the home team was listing at 3-59 and with the removal of Handscomb in the immediate aftermath of tea – a victim of a full, in-swinging delivery from Anderson that pinned him deep in his crease – it was left to Smith and Marsh to mount a salvage job.
Those who optimistically believed the pitch that was variously described on day one as a "featherbed" (by fomer Australia skipper Steve Waugh) and a "pudding" (by ex-Test quick Rodney Hogg) would magically manifest into a traditional Gabba strip were sorely let down.
Day two of a Brisbane Test is traditionally when the game starts to motor along, the moisture of the first morning baked out and the surface hardening to provide extra zip for fast bowlers and true bounce for batters.
Alas, the sluggishness that emerged as the dominant day one discussion point was back the next morning, and as England's fifth-wicket pair of Dawid Malan and Moeen Ali pushed their union carefully past 50 Smith decided it was time for bold new tactics.
So slowly was the ball rearing from the moribund surface that the short-pitched weaponry of Australia's pace battery was reduced to little more than covering fire, and as they settled into their stride Malan and Moeen repeatedly showed their willingness to counter attack.
They regularly aimed hook and pull shots at Mitchell Starc and Pat Cummins in the knowledge that bouncers which might otherwise threaten their persons were sitting up invitingly, with the only danger being the lack of pace and resultant risk of getting through their cross-bat shots prematurely.
So rather than shelve the short-pitched stuff because of its reduced effectiveness as a shock ploy, Smith instead set a field for a miscue and instructed his quicks to bang the ball into the pitch time and again, asking Malan and Moeen to gorge themselves on the bouncer buffet.
What the ploy lacked in subterfuge it ultimately made up for in results, with Malan tucking in until he misjudged the elevation of a Cummins bumper that flew from his top edge into the grasp of Marsh who had been deployed to the hot seat at deep backward square leg.
It was a dismissal as needless as it was obvious, and its significance was amplified across the subsequent hour.
Gifted a breakthrough against the flow of the game, Australia's belief surged as England's middle and lower orders succumbed.
In the time it took to complete 14.2 overs, the tourists lost their final six wickets for 56 and it was only a spirited 20 from 32 balls by Stuart Broad – who should have been dismissed for about half that score – that lifted them beyond 300 when the average Gabba first innings Test total of almost 400 had beckoned late in the morning.
The collapse that Malan set in train was accelerated by Nathan Lyon, whose off-spin has historically been so devalued on the Gabba pitch that his place in the Test team was habitually questioned leading into each Brisbane match.
Where the quicks found little but lethargy and frustration, the surface offered Lyon extravagant purchase and – in many cases – too much turn to find an edge, so it was fitting that a delivery that spun less than Moeen expected accounted for his wicket just minutes after Malan departed.
Allrounder Chris Woakes suggested he had paid scant attention to Lyon's spells when he aimed an ambitious drive against the turn and was unsurprisingly (to everyone but Woakes) bowled between bat and pad before he had scored.
And sensing that his scoring opportunities were dwindling as England's tailenders entered the fray, keeper and accomplished batter Jonny Bairstow mis-hit an attempted heave over midwicket to present Tim Paine with his first Test catch in his second iteration behind the stumps.
Even if he was closer to square leg when he accepted Bairstow's skied offering.
Jake Ball unfurled a trio of boundary blows in his enterprising 14 before he fell into Smith's leg-slip trap deployed with Starc bowling around the wicket, and then Broad was predictably peppered with bouncers until he finally holed out to provide Josh Hazlewood with a consolation wicket.
Although the only time a blow to the head was struck during Broad's 53-minute knock came when he mis-hit a hook from Starc towards the fine leg rope, where Marsh settled under the catch only to have it burst through his hands, hit his forehead and shoulder before it dribbled beyond the boundary for four.
2017-18 International Fixtures:
Magellan Ashes Series
First Test Gabba, November 23-27. Buy tickets
Second Test Adelaide Oval, December 2-6 (Day-Night). Buy tickets
Third Test WACA Ground, December 14-18. Buy tickets
Fourth Test MCG, December 26-30. Buy tickets
Fifth Test SCG, January 4-8 (Pink Test). Buy tickets
Gillette ODI Series v England
First ODI MCG, January 14. Buy tickets
Second ODI Gabba, January 19. Buy tickets
Third ODI SCG, January 21. Buy tickets
Fourth ODI Adelaide Oval, January 26. Buy tickets
Fifth ODI Perth TBC, January 28. Join the ACF
Prime Minister's XI
PM's XI v England Manuka Oval, February 2. Buy tickets
Gillette T20 INTL Series
First T20I Australia v NZ, SCG, February 3. Buy tickets
Second T20I – Australia v England, Blundstone Arena, February 7. Buy tickets
Third T20I – Australia v England, MCG, February 10. Buy tickets
Fourth T20I – NZ v England, Wellington, February 13
Fifth T20I – NZ v Australia, Eden Park, February 16
Sixth T20I – NZ v England, Seddon Park, February 18
Final – TBC, Eden Park, February 21