With the Ashes now certain to remain in England's hands, the spotlight is falling on the future of Australia captain Ricky Ponting.
He is having a ghastly time with the bat,
the pressure is clearly getting to him
and his team are performing woefully.
But the issue of who should succeed Ponting, and when, is anything but a straightforward one.
The main problem is that there does not seem to be another captain around for them at the moment. There is no-one there hammering on the selectors' door saying: "Look we have a crisis here. Make me captain and I'll sort it out."
Michael Clarke (left) has long been seen as Ponting's successor
Vice-captain Michael Clarke is going through a horror story of almost the same magnitude as Ponting. Clarke does not look like the right person, with the bat at least, to take over the reins. He has no confidence and is averaging only 21 in this series.
There is talk about Cameron White coming in as skipper but it would be very un-Australian to pick a player who does not automatically get into the team. Brad Haddin is another option but I am not convinced he has the right character.
Another issue is what do you do with Ponting if he is not captain any more? It is not the Australian way to have a former captain remaining in the side, yet he is their best player, so what do they do about that?
Before Ponting jumps or is pushed, there are lots of things to resolve.
The only thing they do have in their favour is that after this Test series they do not have another until August. So if Ponting were to go after Sydney, they could delay naming a Test successor and thereby give Clarke time to get back into form.
That Australia find themselves in this predicament is largely down to another superb bowling performance from England on day three in Melbourne, with Chris Tremlett and Tim Bresnan particularly outstanding.
For the first time in this series reverse swing really came to the fore and Bresnan, who has only played two games since September, was superb.
To take the wickets of Shane Watson, Ponting and Mike Hussey was probably the highlight of his sporting career.
It was a spell of brilliant, high-class, reverse swing bowling.
Tremlett did not take a wicket but he certainly deserved to, he bowled with pace and a lovely, consistent off-stump line. He really has come on in leaps and bounds.
There is much more about him as a person and a player. He is much more assertive and more confident and that's there for all to see.
Shane Watson has suggested England were lucky to bowl on a green-top early on the first day, and lucky to bowl on a dry, abrasive pitch second time round, but that is nonsense. The gulf between the bowling attacks is colossal.
Peter Siddle ran in wholeheartedly for Australia and was rewarded with figures of 6-75 but they do not seem to have the control in their attack that England have.
England's bowlers were helped out by some very intelligent field placings from Andrew Strauss.
The captain does not over-attack but he comes up with clever fielding plans, like bringing in the short extra cover that caught Hussey.
You do not have to have rows of slips lined up to have an attacking field, Ian Bell was there at short extra to take a wicket. Hussey was not unlucky - it was a perfectly set plan and it was bowled to with perfection.
England will be delighted to win this match but the message will be clear - the job is only half-done.
They will celebrate retaining the Ashes but they will be absolutely determined to become the first team to win a series in Australia in 24 years.
Jonathan Agnew was speaking to BBC Sport's Sam Sheringham
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