WELLINGTON (Reuters) - World champions New Zealand were challenged for 50 minutes but still ran in six tries to beat Australia 37-10 in Auckland on Saturday and become the first top tier nation to win 18 consecutive test matches.

Less than a year after becoming the first country to win back-to-back World Cups and with a much-changed line-up, Steve Hansen's side bolstered their claim to being the greatest ever rugby team.

Julian Savea scored two tries and Israel Dagg, Anton Lienert-Brown, TJ Perenara and Dane Coles also crossed to help the 2015-16 All Blacks better the record held by the 2013-14 and 1965-69 New Zealanders, and the 1997-1998 Springboks.

"We are proud to have got to 18 wins in a row but we had to work hard for it tonight," Hansen told a news conference.

New Zealand's last defeat was at the hands of the Wallabies in Sydney last year but Australia always faced a tall order to break their 30-year Eden Park hoodoo, even if a single try from Rory Arnold was scant consolation for a spirited effort.

The All Blacks were already assured of retaining the Bledisloe Cup after emphatic victories over Australia in Sydney and Wellington and extended their winning streak on home soil to 45 tests.

They took only six minutes to score their first try, fullback Ben Smith slipping his marker, center Reece Hodge, and sending winger Dagg scampering to the line.

Beauden Barrett missed the extras but four minutes later center Lienert-Brown was running in the second try after Australia winger Henry Speight's attempted intercept left a huge hole in the defensive line.

The Wallabies enjoyed a good deal of territory but were unable to turn it into points until lock Arnold reached over the line with a second effort in the 29th minute.

All Blacks skipper Kieran Read was penalized for a shove just after the score but Hodge was unable to convert the penalty attempt from the halfway line to even up the scores.

CHARGE DOWN

New Zealand extended their advantage when Perenara charged down Hodge's clearance kick and re-gathered to give the All Blacks a 15-7 lead at halftime.

Bernard Foley soon cut that lead to five points with a penalty and four minutes after the break thought he had sent Speight in for a try to level the scores.

Referee Nigel Owens, however, called back play because he adjudged that Dane Haylett-Petty had impeded Savea and prevented him from attempting to tackle Speight.

It was a call that clearly infuriated Australia coach Michael Cheika.

"Obviously I can't say anything because they've got you by the throat," Cheika told reporters.

"I’ve never seen shepherding from behind before. But we can only call it a turning-point if we lose by less than one score."

Savea's name was the next on the scoresheet in the 54th minute as New Zealand typically exploited turnover ball inside their own half to set the hulking winger for his 44th try in 49 tests.

The 45th came 12 minutes from time, again from turnover ball, and with a 32-10 lead, any nerves the home side were experiencing had dissipated and Savea sent Coles over for the final try of the night after 74 minutes.

The All Blacks now head to face Ireland in Chicago and Dublin as well as Italy and France, looking to inch towards the overall test record held by Cyprus.

The Cypriots racked up 24 straight wins by beating the likes of Austria, Bulgaria and Luxembourg before their streak was snapped by Latvia in November 2014.

(Reporting by Nick Mulvenney in Sydney; Editing by John O'Brien and Ed Osmond)