New Zealand coach Scott Robertson praised his team's mental resolve after the All Blacks extended their dominance over Australia in damp conditions on Saturday.
An injury-ravaged All Blacks scored four tries to one in an 28-14 triumph in front of 60 113 fans at Perth Stadium.
The result meant world champions South Africa need to beat Argentina in London later on Saturday to win the southern hemisphere championship.
After patchy form during the tournament, heightening pressure on Robertson, the All Blacks produced a stirring performance against a Wallabies side striving to send off retiring James Slipper on a high.
But the visitors stood firm against an early onslaught before slamming the door on a late Wallabies rally.
"We stayed in the game, took our opportunities and that was really important going into the second half," Robertson told reporters.
"The mental toughness and the grit that was showed to stay in the match... in past games, we probably would have let teams back in.
"The bench that came on made a big difference and we managed to finish it...real tough game."
Midfielder Quinn Tupaea broke the game open with back-to-back spectacular tries late in the first half before teeming rain slowed the play down after the interval.
"He's pretty robust, tough and physical," Robertson said of 26-year-old Tupaea.
"Was great to see him with his ball carry and he'll be better for that test."
The All Blacks continued their stranglehold over their rivals after notching a record 11th straight victory over the Wallabies.
"We knew the importance and how big this match was for them, especially with the emotion of James's last game," Robertson said, with the All Blacks having previously won 10 straight tests against Australia in 2008-10.
"We knew Australia have got momentum and there's a little bit of hype around it.
"We came prepared for that and happy with the results."
The sweep of the Bledisloe Cup will give New Zealand confidence ahead of their northern hemisphere grand slam tour.
"It's pleasing to finish the Rugby Championship with a win like that," All Blacks skipper Scott Barrett said.
"Wasn't pretty, but throughout this Rugby Championship we learnt we need to front up every week.
"We want to have a refresh before we head up north and chase the grand slam."
‘EVERYONE'S OLDER BROTHER': SLIPPER BOWS OUT IN WALLABIES LOSS
Australia failed to produce a fairytale finish for stalwart James Slipper on Saturday against New Zealand but the Wallabies' most capped player walked away with plaudits and plenty of admiration.
The Wallabies fought hard in wet and slippery conditions at a sold-out Perth Stadium before falling 28-14, their 11th straight loss to the All Blacks.
All eyes were on 36-year-old Slipper, playing in his 151st and final test after announcing his retirement during the week.
Slipper produced a trademark physical effort, helping the Wallabies start strongly as they controlled play for chunks of the first half despite trailing 17-9 at the interval.
Slipper was substituted just after the resumption, walking off to hearty applause from the crowd in the same city where he made his debut against England in 2010.
"He's pretty much everyone's older brother in the team and we love him," Wallabies captain Harry Wilson told reporters.
"He always says the right thing to you at the right time and he's always there offering advice.
"We definitely will really miss him around this group."
Slipper, who captained Australia 15 times, departs after a decorated career.
He is one of only three Australians, along with George Gregan and Adam Ashley-Cooper, to play at four World Cups.
He resisted the temptation of a 2027 World Cup on home soil.
New Zealand's players and staff warmly embraced Slipper after the match.
"It was great to be a part of the occasion," All Blacks coach Scott Robertson said.
"I know they'll be disappointed they couldn't do it for him, but won't take away from the hell of a career he's had.
"He's such a good man, and sort of the essence of why we play rugby."