New Zealand collapsed in limp fashion to a 4-2 defeat at the hands of the Fijians, and in the aftermath Blair attracted the ire of many with his nonchalant reaction, which included him suggesting the loss wasn't a negative for this side.
McClennan, who masterminded one of the greatest Kiwi victories of all time when he coached New Zealand to a 24-0 shutout of the Kangaroos in the 2005 Tri Nations final, admitted on Sky TV that he shed tears following the historic loss and was perplexed by Blair's words.
"I'm surprised by how 'Blairy' talked at the end there; it's bizarre," McClennan said.
"I know Blairy. He's just got it wrong, whoever is teaching him this, you've got it wrong, you've got to wear your heart on your sleeve all the time, you're representing your country."
After leaking five tries through the second half of last week's 28-22 loss to Tonga, New Zealand again shot themselves in the foot against Fiji with 13 errors, several of which occurred while coming out of their own end.
There were also a glut of needless ruck penalties which stemmed from the Kiwis' inability to match it with Fiji in the middle of the park.
McClennan highlighted shortcomings in New Zealand's toughness when faced with adversity, and expected coach David Kidwell to pay the price.
"Unfortunately this Kiwi team has a soft underbelly, they don't rise up and play tough and they are not an intelligent team," McClennan said.
"Just a dumb performance… it's a dumb performance when you try and solve problems on your own. There's a lack of leadership through the team.
"There needs to be a thorough analysis of what's going on with the Kiwis and New Zealand league.
"I think it probably will [result in Kidwell no longer being coach], and I am sad to say that, but in this business, you live by the sword, you die by the sword."
Saturday night's defeat marks the only time New Zealand have failed to advance to the semi-finals of a World Cup under the current play-off format.
