"We have to go away and look at ourselves even though we are hurting. It's not something we have had to do very often but it still sucks."
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All Blacks skipper Richie McCaw was similarly disappointed, but could pinpoint where the game went wrong for the visitors.
"We made it a little bit easy through some poor decision making and they took their chances ... we've won games in the past because we got that right, but tonight we didn't and the Wallabies did," said McCaw, who tied the record for the most test matches played in the contest last night.
Richie McCaw looks on after the Wallabies score. Photo / Getty
McCaw pointed to the high error rate of his troops, calling it "inexcusable".
"It's a bit disappointing," he said. "We've got to make sure we turn it around. We're good enough to execute better. No point panicking.
"We got ahead on the scoreboard and needed to get things spot on and make the Wallabies do things they aren't accustomed to. The feeling I've got is that we made poor decisions and they took their chances."
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Hansen was also critical of the errors, putting it down to a mix of pressure and sloppy decision making from his side.
"Pressure can create errors, but I think some of it was forced on us by our own decision-making when we weren't under pressure," said Hansen.
"We were in the game all through it but we had period for 10 minutes when we made poor decisions," he said. "Nugget [Aaron Smith] being sin-binned. We turned the ball over when Codie Taylor kicked it through and we missed a bread-and-butter tackle on a halfback. These are the moments you have to get right and we didn't."
Despite the loss, Hansen still found some positives to take away from the game.
"We've got some things we can be happy with. The debut of Nehe Milner-Skudder was very impressive.
"We've lost games before and it doesn't mean we've all of a sudden become a bad team. We just have some things we need to tidy up and we'll get back to Auckland tomorrow and start that process."