Alastair Cook is determined to continue as England captain — even if he loses the Ashes 5-0 — until someone instructs him otherwise.

Cook appeared shell-shocked as he addressed his post-match press conference after England’s miserable tour had hit a new low at the MCG.

But he still had enough in him to defend his under-performing players’ Test pedigree, the coaching staff’s ongoing aptitude for their jobs and to underline his own readiness to carry on.

A fourth successive defeat came by eight wickets after Chris Rogers (116) and Shane Watson (83no) completed Australia's fightback from a first-innings deficit to once again trounce the tourists.

It was perhaps understandable therefore if, needing yet another action-replay take of his previous statements of resolution in Brisbane, Adelaide and Perth, Cook was not quite able to do it all one more time with feeling.

Nonetheless, as the inevitable pointed questions kept coming about his team, his leadership and their management, he put up a stout defence.

Cook made it clear he is no quitter, but understands judgments about his future as captain — little more than a year into his tenure — may yet be taken out of his hands. “I’m 100 per cent wanting to carry on.

“If someone makes that decision, and says ‘we think there’s a better man’ or ‘you’re not good enough to do it’ then I have to take that on the chin — because as a captain, you’re responsible for the team.”

What, though, of Andy Flower and his back-room specialists — such as batting and bowling coaches Graham Gooch and David Saker?

“I’m fully supportive of our coaching staff.

“We’ve had some fantastic results ... it wasn’t so long ago we won in India with this same coaching staff, against Australia with the same coaching staff.”

Their continued involvement may well depend on the outcome of a date with destiny in the final Test, which starts in Sydney on Friday.

Cook knows he can still have a say then, but must leave the consequences in the hands of others.

“They’re decisions which can be made later and down the line.

“That’s why people higher up than me are paid money to make those decisions.

“If they think that’s the way to go — with all those decisions, captain, coach, whatever — then that’s the way it is.

“We can only concentrate on what we do from now, trying to regroup and put in a performance in Sydney.”

Cook is in no doubt that a team of mixed experience — a nucleus of previous Ashes winners, himself included, along with some yet to establish Test credentials — can succeed for England.

There has been precious little evidence of that since they arrived Down Under, fresh from a 3-0 home success against Australia and with a fourth consecutive Ashes series victory on their minds.

But at the suggestion his current crop have either lost their edge, or are never going to have it, he said: “I think that’s a very big shout.

“We’ve some very good players in our dressing room.

“We’ve some record-breaking players who will have some fantastic days left in an England shirt.

“I know that for sure, and we’ll be praising them when they do that.

“We need that now, in Sydney ... we need an outstanding 100 or an outstanding ‘five-for’.

“That’s what turns around a team that is struggling like we are.”

It was hard to find any consolation in Melbourne, after England had let a favourable position slip so badly in a second-innings collapse to 179 all out that Australia instead not only won but did so with more than four sessions to spare.

“It’s very disappointing.

“We worked very hard for two-and-a-half days to get ourselves in that situation.

“When you don’t follow it through, it hurts even more.

“No-one means to get out ... I know all the guys out there are trying as hard (as they can).”

“A lot of questions are always asked when you lose lots of wickets in clusters.

“You know it’s not the right thing to do. You’re not trying to do it.

“You have all these meetings about building partnerships, and you know the first 20 runs of a partnership are crucial, but ... the players aren’t performing out in the middle.”

England were still optimistic going into the final day, defending 231 with the hosts on 30 for none, but dropped Rogers on 19 and 81 — and his opening partner David Warner for good measure too.

One theory is that, under the earnest Flower and willing Cook, intense England are piling extra pressure on themselves.

The captain is having none of that. “It is a serious business.

“A lot of people come a long way to watch us play, and we appreciate that.

“It’s our careers as well, so it is serious.

“If I knew the answer, I would be doing as much as I can about it.

“The bottom line is we haven’t been good enough.

“When we left England, we had high hopes of doing something very special.

“I did say at the time, we’d have to play some very good cricket if we wanted to achieve that — and we haven’t done that.”