Bledisloe Cup 2015: Key Takeaways from New Zealand's Victory over Australia

New Zealand thrashed Australia 41-13 to retain the 2015 Bledisloe Cup on Saturday.

Australia won the first game in the series to give themselves a chance of winning the cup, but the All Blacks ran rampant over the Wallabies to keep the trophy for the 13th consecutive year.

Here are the key takeaways from the match ahead of the Rugby World Cup in England next month.

New Zealand Are in Great Shape 

Australia's 27-19 victory over the All Blacks in the Rugby Championship earlier in August gave New Zealand an unfamiliar air of vulnerability, but they showed their true colours in Saturday's majestic performance.

Dane Coles, Conrad Smith and Ma'a Nonu (two) chipped in with tries, while Dan Carter scored two penalties and five conversions for the All Blacks.

Anthony Au-Yeung/Getty Images

Smith, Nonu and Carter, along with fellow veterans Richie McCaw, Keven Mealamu and Tony Woodcock, lifted the trophy for the last time as they played their last match at Eden Park.

Sports journalist Alex Shaw was full of praise for McCaw, who reached a milestone on Saturday:

The All Blacks legends are bowing out on a high though, as their exceptional form and unrivalled experience give Steve Hansen's side an excellent chance of winning the World Cup.

After the disappointing defeat to the Wallabies, New Zealand rediscovered the pace and power that punctuate their game, and the confidence that Saturday's victory will have given them is an ominous sign for their World Cup rivals.

Quade Cooper's Struggles Against the All Blacks Continue

As the Guardian's Rajiv Maharaj notes, fly-half Quade Cooper has endured a torrid time in his international career when facing New Zealand.

Cooper infamously put in a shocking performance in the 2011 World Cup semi-final against the All Blacks, and the Auckland-born 27-year-old fared little better on Saturday.

The fly-half had kicked two penalties in the first half for the Wallabies as they went into half-time down 13-6, but disaster struck in the 48th minute when Cooper made a high tackle on Aaron Smith:

"

Yellow card for Quade Cooper for this high shot on Aaron Smith. https://t.co/rfF04F1Nmm

— EatSleepRugby (@Eat_Sleep_Rugby) August 15, 2015"

Cooper was subsequently sin-binned for the foul, which handed the All Blacks a penalty try.

New Zealand went over twice more to run away with the match while the No. 10 sat on the sidelines.

Should the two sides meet in next month's showpiece, Cooper needs to stay on the bench. If he makes the squad, that is.

Michael Cheika Must Ditch His Rotation Policy

Australia coach Michael Cheika made six changes to the side that overcame New Zealand in the first fixture, with the likes of the effective David Pocock and Matt Giteau missing out.

Hagen Hopkins/Getty Images

Per the Australian Associated Press (via the Guardian), the coach said he was "really keen on guys being able to slip in and out."

However, as important as it is for the whole squad to be able to fill in if needed, rotation should not come at the cost of silverware.

The World Cup is of course the priority, but having such an excellent chance of reclaiming the Bledisloe Cup for the first time since 2002, Cheika should have gone all out for the victory.

Fox Sports' Greg Clark still holds some optimism for the Wallabies' chances at the World Cup, but he concedes there is work to do with the tournament kicking off on September 18.

First and foremost, Cheika must avoid rotating for the sake of it. As they showed on Saturday, Australia need their best players in order to compete with the world's best.