New Zealand's Dan Carter revealed that their defence let them down against a fired up Argentina on Sunday.
The All Blacks were forced to come back from a 12-16 deficit to eventually overpower the Pumas 26-16 in a pulsating affair at Wembley Stadium.
Argentina played with full of confidence and broke the defending champion's line on many occasions, putting them on the back foot.
"We were falling off tackles, tackling too high and they were getting in behind us and we just couldn't get our defensive line set," revealed the All Black pivot on stuff.co.nz
"We couldn't come forward, so we were forever backtracking. Credit to Argentina, they attacked extremely well through our heart and we couldn't get any momentum because we were tackling too high."
The Crusader number ten indicated that the refweree Wayne Barnes had told the players beforehand that he would be harsh at the ruck as he wanted a clean ball for a fast game.
"We knew before the game the referee's expectations," added the 33-year-old.
"They don't want guys hanging around on the wrong side of the ruck and they want the tackler and the assist tackler out of there, so that's going to mean quick ruck ball."
Meanwhile, replacement number ten Beauden Barrett said that the All Blacks created plenty of scoring opportunities, but failed to capitalise on all of them.
"We created enough opportunity," said the Hurricanes flyer.
"We missed a few of those opportunities, but the pleasing thing was we put ourselves in those positions."
New Zealand next face Namibia at the Olympic Stadium in London on Thursday.