Ryan Crotty was among the try scorers as New Zealand beat Australia (Rick Rycroft/AP)

The All Blacks led 40-6 at half-time before winning 54-34.

A second-half rally was not enough for Australia as they lost the opening Rugby Championship clash to New Zealand.

The Wallabies were facing severe embarrassment in Sydney as they trailed 40-6 at half-time, and the All Blacks extended their lead to 54-6 after the break.

The visitors’ summer exertions against the British and Irish Lions perhaps caught up with them in the second period and Australia cashed in, scoring 28 points, but New Zealand ran out comfortable 54-34 winners.

It will go down as a terrific result for Steve Hansen’s men, who were home and hosed by the interval.

Liam Squire had them in front 10 minutes in with the first of 12 tries on the day, but two Bernard Foley penalties kept Australia in the hunt at 7-6.

New Zealand then cut loose. Rieko Ioane scored twice in three minutes and Ryan Crotty also crossed for what amounted to three tries in the space of 420 seconds.

Beauden Barrett, who faced questions about his kicking in the week, converted two of them, and then tagged the extras as Sonny Bill Williams and Crotty dotted down before half-time.

The 40 points New Zealand had at the whistle were a record for them in a half against Australia.

A first Test try for Damian McKenzie continued the rout after the restart and Ben Smith added another, before Australia were able to mount a comeback.

Curtis Rona, Tevita Kuridrani, Kurtley Beale and Israel Folau all crossed, with Foley converting them all, but it mattered little.

Australia coach Michael Cheika: “We’ve got to acknowledge what we did wrong first of all and then say ‘Okay, we’ve got to fix that thing or those two things or whatever they might be’ and then go to it and do it. This group of players here, they’ve got a very strong connection. This is a roadblock in front of us, of course, and it’s going to knock us down but it’s not going to stop us.”

New Zealand coach Steve Hansen (on Jerome Kaino): “It’s a personal thing that he and his family have to deal with. We all know what the problem is and he’s got some stuff he’s got to deal with. Once he’s dealt with that, we’ll make some decisions.”