Hansen, the All Blacks coach, said although Australia had just been whitewashed by England it was still a good Australian team.
"I think the Wallabies did front up. It is a good England side. The bounce of the ball has not gone their [Australia's] way and they are a good side,'' he said.
"It would be very foolish of us to underestimate them. They will be hungry.''
Hansen said he was very happy with the performance of his side in the just completed series - whitewashing Wales - and the players new to test rugby had performed well.
"You are always nervous when you start a new season. Have you got it right? Have you got your selections right? [Is] your environment right? The only way you really know that is when you are under pressure in the test match.
"We have come out of that pretty good. Having lost all of those players made it an exciting challenge, not only from a coaching point of view but for the players.''
The success of the side did not happen overnight but different factors contributed to the victories.
"To lose that many caps [818] but replace them with people who have played 50 tests and then a lot of the guys have played 20 to 30 test matches. So they understand what test rugby is about.
"We have brought guys into the leadership group really early so they know what it is about . . .
"Our nursery is fantastic. The Super competition is a lot better competition that people give credit for. It has a combination of all three things - running, kicking and physicality.''
Hansen, though, was not singing the praises of everything, saying it was hard to believe two of the members of his squad played on Saturday and were on a plane to South Africa yesterday to play for the Highlanders next weekend.
"It is tough for the athlete, bordering on ridiculous, really. There is a guy getting on a plane today to go to South Africa, the day after a test match.
"But that is the state of the nation - that is the state of our competition at the moment. So until we get the global season sorted that is the sort of the stuff we have to put up with. It is no-one's fault.''
He said an integrated global season would have a huge pay-off for everyone and grow the game.
"Look at Ma'a Nonu, who was outstanding last year and why? Because he got a decent pre-season. He broke his arm [but] he was able to then play outstanding football for 12 months of the year.
"We know 12 weeks [rest] is the minimum. Ideally you want 14 to 16 weeks . . . it is difficult to get that because we have not got the window. Up north, their club and international rugby is a lot more bash than we've got. The difference between the two - one is a running game and the other is a physical, dour game.
"It needs a genuine desire of everybody. French clubs use 47 out of 52 weeks. That makes it hard to get a pre-season.''
The All Black squad broke up yesterday and would regather with the next game against the Wallabies in Sydney on August 20.
Centre George Moala damaged ligaments in his elbow while Ryan Crotty took a blow to his calf and lock Charlie Faumuina injured his knee.
Whether they can play for their Super rugby teams this week was unclear yesterday.