Robbie Deans says the All Blacks of 2017 have a fragility about them but opponents had better make the most of it now.
The Deans-coached Barbarians were the latest team to cause the world champions some grief this year before squandering a healthy lead to lose 31-22 at Twickenham.
New Zealand's performances and results have dipped beneath their lofty standards set since Steve Hansen took charge in 2012.
They've lost twice and drawn once from 12 games, while several wins have been far from accomplished performances.
Hansen agrees chinks have been exposed by their need and desire to blood new faces this year, with the hope of building depth over coming seasons.
Japan-based Deans says the All Blacks are lacking a clinical edge.
"They're giving teams a little sniff, they're giving teams encouragement," the former Crusaders and Wallabies coach said.
"They gave us a fair amount of encouragement in the first half.
"The critical thing is where they go from here. I've got no doubt they'll go that way (pointing up) because that's what they do. It means too much to them."
Deans said few other nations, if any, would have the capacity to keep winning while functioning with a revolving door selection policy.
He says if Hansen hadn't begun regenerating, it may have backfired on the All Blacks at the next World Cup.
"They're vulnerable but they're still travelling well, that's what they do," he said.
"The players have had a taste of it and they want more. They're hungry and they just bubble out at the top.
"They're in no hurry to give up their status as the best team in the world."
Meanwhile, Deans showered praise on Crusaders first five-eighth Richie Mo'unga, who produced a bright performance for the Barbarians.
Mo'unga, a brilliant performer at Super Rugby and NPC level this year, is one of five players who is joining the All Blacks squad in France.
The introduced group are likely to play in a match on November 14 against a France XV.
"He showed he's capable of playing at this level. And it will happen, it's quite simple," Deans said of Mo'unga.
"He'll get there and experiences like this accelerate that."
