Blink and you miss it in the frantic world of T20. Opportunity has knocked twice for Australia in this series - with a thumping great battering ram in the series opener on Friday, and with a polite rap of enquiry in the closing moments two days later. And twice England have peered over the ramparts and drawn up the drawbridge, to take a 2-0 series lead with one to play, and leave their opponents somewhat non-plussed in their first competitive outing since March.

But this third outing, however, is a dead rubber with more riding on it than might ordinarily be the case. Next month's T20 World Cup may be on the back burner, and so this is not the opportunity for fine-tuning for which it had originally been earmarked, but the ancient annals of Anglo-Australian rivalry love a chance for some bragging rights to be put up for grabs.

And so it will prove on Tuesday, where England know they will not be satisfied simply to leave with the series trophy in their grasp. The World No.1 ranking is the true objective for Eoin Morgan's men, an accolade which passed temporarily to them after their six-wicket win on Sunday, but which will be snatched back by Australia if they can end their series on a high.

It may be a broadly meaningless bauble controlled by a mysterious ICC algorithm, but the allure of being top dogs is more than merely cosmetic for the hosts. Just as was the case in their four-year journey to becoming the 50-over World Champions, the No.1 spot was a rite of passage that Morgan, and the then-coach Trevor Bayliss, used almost as a stress test.

England, they realised, needed to know the full texture of expectation, for until they had learned what it meant to be a team with a target on their back, they could not be ready for the crunch moments that, sure enough, would await them come the biggest stage of all.

So this contest is sure to matter, in the same way that England's whitewash-sealing win at Old Trafford in 2018 mattered. Right up until the moment that Jos Buttler sealed an excruciating one-wicket win with a brilliant unbeaten 110, Australia had looked set to secure a consolation victory that would have been out of kilter with the fare that had gone before it.

Buttler, however, will not be present for this contest. He has been granted leave to visit his family, having excelled in the opening two games, and Morgan too cannot be a complete shoo-in either, having suffered a very awkward-looking finger dislocation in the field on Sunday - not that it prevented him from batting, albeit briefly, in the run-chase.

They may be a huge pair of personalities to lose from their starting line-up, but England will not mind too much if they are forced to dig a touch deeper and rely on less prominent members of their line-up to front up with the crucial contributions. For as Australia's own struggles to find a serviceable middle order have shown, sometimes the hardest part of T20 squad-building is giving meaningful opportunities to the men outside of the prime positions.

If, in the circumstances, the No.1 ranking has to be delivered by the likes of Tom Banton, Sam Billings (and of course the ubiquitous Dawid Malan), then England will consider this series a job very well done. Especially as you can be sure, in spite of the errors that have derailed them up to this point, Australia will not be relinquishing their hold without a fight.