Mehrtens says injury-hit All Blacks vulnerable
New Zealand's Aaron Cruden kicks a penalty during their rugby union Test match against the Wallabies in Sydney on August 16, 2014 - by William West
The Wallabies impressed in a 12-12 draw to start the Rugby Championship in Sydney last weekend, preventing the All Blacks notching a world-record 18th consecutive Test victory.
The Wallabies have not won at Eden Park since 1986 but Mehrtens said Ewen McKenzie's men had shown enough in the stalemate to suggest they can breach the Auckland fortress.
"Despite a lot of talk about the All Black response at Eden Park, I see the Wallabies as an even bigger threat this week as they eye a great chance to snap a second win streak in as many weeks," he told Fairfax Media.
Mehrtens, who played 70 Tests for the All Blacks and helped guide Australia's NSW Waratahs to the Super 15 title as kicking coach this year, said the Wallabies rediscovered how to be gritty and tough in Sydney, particularly in defence.
He said they were brimming with confidence as they chase a win in Auckland that would keep alive their dream of a first Bledisloe Cup series win since 2002.
"That they were so disappointed about the draw is also a good sign," he said. "That shows they're not willing to settle. They want that All Black scalp."
New Zealand are likely to be without seasoned campaigners Nonu and Kaino after both picked up niggling injuries to their shoulder and elbow respectively during the Sydney Test.
Neither participated at training on Tuesday and assistant coach Ian Foster said both appeared "highly unlikely" to play.
"We'll know more tomorrow but the signs are looking that they won't be playing on Saturday," he told reporters.
New Zealand will name their team on Thursday, with Liam Messam expected to replace Kaino at blindside flanker and Ryan Crotty slotting in for Nonu in the centre.