The dam wall has busted. The centre could not hold.

For the first time in this otherwise outrageously tight Ashes series, a day has been thoroughly dominated. Each of the first three Tests had been defined by days that fluctuated almost hourly, with ascendancy hacky-sacked around with reckless abandon. 

But no more. On day two of the fourth Test at Old Trafford, England bullied Australia into submission and made a point of not letting up. 

It was Australia's worst day of this series by some distance, and one that has tipped the balance towards England for the first time since day one at Edgbaston.

Zak Crawley was the chief protagonist, his fearless and naturally expansive batting something that will live long in the memory. He had been threatening an innings like this all series, the day when everything would fall his way and every confident flash of his blade would be rewarded.

Even Crawley himself might have thought 189 from 182 and the fastest 150 in Old Trafford's Test history was a bit too far-fetched to hope for. Very few batters do things like that to Australia, completely ripping the soul out of the best bowling attack in the world.

The early fortune he enjoyed seemed to only accelerate the breaking of Australia's spirits. Crawley was given out LBW before lunch but was saved by DRS. His inside edge was worn out but the deflections avoided the stumps until long after his job was done.

But once the early scares were survived, Crawley was imperious. He rarely played a shot you wouldn't find in the dustiest of batting textbooks, but his timing and power were something to behold.

And if he couldn't find the boundary, he simply took the ones and twos on offer. It was an ODI innings, measured to perfection, against an opponent so lost inside its own head it needed Leonardo DiCaprio to get it out.

Because for as good as Crawley was, Australia was just as poor.

The tourists were muddled and ineffective in every aspect of their play, surprisingly led in incompetence by Pat Cummins.

Australia's captain had a 15-minute period immediately after lunch in which he seemed to be on another planet. He missed the chance to dismiss Moeen Ali twice, firstly by completely misreading the flight of a ball at mid-on and then by spilling a relatively simple chance at mid-wicket.

None of us could claim to be able to read Cummins's thoughts at that moment, but to the uneducated he seemed a man distracted by the situation, stuck between responsibilities and just a little paralysed by an ever-worsening situation.

But it wasn't just Cummins. Australia bowled poorly, far too straight to Crawley and without consistency across the board. This all-pace attack tried to hit lines and lengths for a while without success before deferring to the familiar short-ball strategy, also without success.

The Aussies bowled more no balls than they have in any other innings so far this series, and saw their sloppiness in the field culminate in some embarrassing overthrows late in the day.

By the time Crawley and Joe Root had been dismissed — both by deliveries that kept incredibly low, in yet more discouraging news for Australia's efforts to save the game with the bat — Australia's wheels had come off and were rolling away down the M62.

It was all just about as bad as Australia could have imagined. So what happens next?

Australia prays for rain, that's what. And those prayers might yet get answered, as the forecast for the next two days especially suggests a fair bit of play is going to be lost.

But even if rain is to cost England a large number of overs, its complete and utter dominance on day two of this Test means Australia will still need to work incredibly hard to save this Test and retain the Ashes in Manchester.

England will likely look to take its lead to somewhere around 100 and then send Australia back in, at which point the Aussies are batting for their lives.

If this series was to get back to 2-2, setting up a decider at The Oval for this Australian side that is looking ever more battered, bruised and broken with every passing day, England would be heavy favourite.

The ultimate Bazballing would be there for the taking. Why settle for chasing down a total to win a match, how about chasing down a 2-0 deficit to win a series?

Or Australia could fight like hell here in Manchester, maybe with the help of some timely rain, and get the matter of Ashes ownership settled before even returning to London.

England has the advantage, but for Australia the real battle is only just beginning.