SYDNEY (REUTERS) - Rieko Ioane and Ryan Crotty both crossed twice, as New Zealand ran in eight tries in a brilliant display of running rugby to demolish Australia 54-34 in the Rugby Championship opener on Saturday.

The world champions extinguished any chance of an upset with three tries in seven first-half minutes and continued to slice through the home defence almost at will in the opening 50 minutes, leading 40-6 at half-time, to begin their title defence in some style.

Liam Squire, Sonny Bill Williams, Damian McKenzie and Ben Smith also scored tries as the All Blacks brushed off the disappointment of the drawn British and Irish Lions series and a string of off-field distractions.

The Wallabies scored four tries through debutant winger Curtis Rona, replacement back Tevita Kuridrani, centre Kurtley Beale and full-back Israel Folau but they came in the second half, once the game was already beyond them.