But McCaw has apparently moved on in the years since the All Blacks 2007 World Cup exit, and rather than harbouring any ill-feeling towards Barnes, he accepts his side were the architects of their own demise.
"If you keep looking at other people for their mistakes to cover up your problems then you are in trouble," McCaw said in an interview with the Sunday Times.
"From a player's point of view I just knew we hadn't played good enough. I have had quite a lot to do with Wayne since then and he is a top bloke. He does it for the right reasons and that's all you want from the fellow in the middle."
That opinion is in stark contrast to the view McCaw expressed in his best-selling biography of 2012, Open Side, where he was openly critical of Barnes' appointment and subsequent quarter-final performance.
"I don't blame Barnes, but I do blame the people who appointed the most inexperienced referee on the roster to a RWC quarterfinal between the hosts and the favourites. I thought both teams deserved a referee with experience," McCaw said in his book.
"My beef isn't with Barnes so much as with his inexperience. This was Barnes' biggest game by far. On the big stage, an inexperienced referee is likely to become so afraid of making a mistake that he stops making any decisions at all.
"By the end of it, I thought Barnes was frozen with fear and wouldn't make any big calls."
McCaw's interview with the Sunday Times also revealed a humble character, seemingly unaffected by his status as the most-capped international player and the All Blacks 2011 World Cup triumph.
His easy-going and laidback demeanour was typified in the direct quote: "I don't want people to think I come across any different to any other Kiwi bloke. I want them to see me as someone who plays rugby and does that okay. It's not hard to be like this if you just be yourself and I've always had a good bunch of mates outside of rugby that are pretty quick to knock you back to size."
With speculation swirling that he is set to retire following his fourth World Cup campaign, McCaw is grateful to be leading the All Blacks on their quest and explained his 2012 sabbatical was integral to him being fit and ready to compete at his best.
"I was thinking the four years leading up to the last one was pretty intense and I was like, 'How the hell am I going to do that again? Do I really want to do that again?' The break made me realise I still enjoy it and I still had a chance of making the team. And the team in 2012 carried on with the high standard and that excited me quite a lot. Having a good relationship with Steve Hansen was also important," said McCaw.
"We talked about it and he was pretty open. He said if your form drops to a point where you are in trouble about being picked we are not going to get to the point where it becomes a horrible situation. We will sit down and talk and make sure the right decision is made for everyone. That gave me a lot of comfort as well."
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