Back as defence coach with England, he's adamant the lesson has been learned - to not underestimate an unimpressive looking Australian team.

Heading into the 2003 semi-final in Sydney, Mitchell's All Blacks would have enjoyed similar favouritism to what this week's England team have in Oita.

In both tournaments, Australia flattered to deceive in pool play.

Yet 16 years ago they suddenly came alive, given belief by Stirling Mortlock's early try before defending with their lives, allowing George Gregan to ultimately bellow "four more years" to his crestfallen opponents.

Mitchell was axed and later admitted he was too raw to have held the post.

After a varied string of coaching appointments, fate led the 55-year-old to join England head coach Eddie Jones as an assistant 12 months ago.

The picture he has of innovative Australian teams remains, making it difficult to set up a foolproof defensive plan.

"The first thing that we acknowledge is that the Wallabies are a very clever football team. They will be clever on the weekend," Mitchell said.

"At the end of the day, having witnessed a number of teams play against Australia ... they have always been highly intellectual in the way that they play the game."

Wallabies coach Michael Cheika has endorsed a ball-in-hand approach in Japan, attracting critics who believe there isn't enough variety to crack open defences.

Mitchell doesn't believe it's a bluff from the Australians.

He expects them to do minimal kicking in general play, in turn starving the English of possession.

"They just love moving the ball -- I think that's the Australian way as well," MItchell said.

"That's to me very much their mentality and always has been and always will be.

"I'm sure there'll be a few surprises. Like any defensive system, you cannot defend for all the space but it's up to Australia to find it."

Australian Associated Press