Australia's lack of composure proved costly in the second half of their Bledisloe Cup defeat to New Zealand, according to coach Michael Cheika and captain Michael Hooper.

The Wallabies held a narrow lead at the break as they largely kept the All Blacks at bay in the opening 40 minutes, but Steve Hansen's men accelerated out of sight following the restart, romping to a 38-13 win. 

And having shown that they could compete with the world's best, Australia's failure to maintain their level of performance, playing with the same attitude and mentality, was of frustration for Cheika and Hooper.

"There was too much ball given back to the opposition, both from set-pieces and general play," Cheika told a news conference.

"We've got to stay at it. When things don't go your way or don't happen like you want them to, you've just got to keep coming and see where it goes from there.

"Even when we made some really good attacking raids in the second half, we tossed the ball away. We should have kept doing what we need to do."

Hooper continued: "It's really disappointing, isn't it?

"We were really building some nice phases and it's particularly [disappointing] when you get down the other end and just throw the ball away, not backing what we can do. If we held that for one or two phases of play, we were probably walking one in.

"We stifled their attack in the first half quite well. The way we defended was quite good. We put them under pressure and they spilled quite a bit of ball. That was pleasing.

"The frustration is that we went away from that."