Brendon McCullum took full responsibility after England's Ashes series defeat by Australia was confirmed, conceding his plans "didn't work".

Australia retained the urn on Sunday after bowling the tourists out for 352 to seal an 82-run victory in Adelaide.

It gave Australia an unassailable 3-0 lead in the series, which England began with successive eight-wicket defeats, while their spirited display in the third Test came too late to keep their faint hopes alive.

England coach McCullum knows he will come under scrutiny as a result of the series defeat, but acknowledged the buck stops with him.

"It is disappointing when you lose. I'm sure there will be plenty of questions asked, and rightfully so," he said. "We haven't got everything right. I haven't got everything right as a coach, and I put my hand up for that.

"I have been very strong about the conviction we had and our preparation and, for us, it was a matter of trying to replicate what we have done in series that have been successful for us away from home. Maybe we didn't get that right, and I'll acknowledge that.

Australia win by 82 runs and retain the Ashes. pic.twitter.com/YtIf1CzmmU

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"Ultimately, you are responsible for how you get your side ready and how you prepare them. We are 3-0 down, so you would probably say there was room for change there.

"Again, you put your hand up as a coach and say you might not have got that right. At the same time, I felt it would give us our best chance because it has previously. Sitting here 3-0, it didn't work."

England lost the Ashes series in a record-equalling 11 days, and captain Ben Stokes felt a lack of consistency from his side in all areas was a crucial factor.

"It obviously sucks," he added. "Knowing now that we can't achieve what we set out to do here is obviously very disappointing.

"It's quite simple to me that Australia have been able to execute batting, bowling and fielding a lot more than us on a much more consistent basis.

"They've been able to execute everything a lot better than us [for] a much more consistent period of time. We've had moments where we've been very good, but Australia have been a lot better than us over a much longer period of time in this series so far.

"We know the plans that work out here. We've just not been able to execute those plans for long enough.

"We did it in moments and did it in passages, but you just can't be so poor with your execution as consistently as we have been over these first three games – and particularly with the ball. When you're off here, it gets punished, and we've seen that."