The reaction of some fans at International Stadium Yokohama during the All Blacks' haka has been criticised as "disrespectful".
The All Blacks begun their World Cup defence with a big victory over rivals Springboks in a thriller.
However, during the All Blacks' traditional challenge before the clash, a bunch of fans sung during the haka which was audible through the TV broadcast.
The reaction to the kapa o pango was met with a strong reaction on social media, with many criticising the behaviour of the fans at the stadium.
"The f****** disrespect," said one fan on Twitter. "When south Pacific teams haka before the game it's the equivalent of a national anthem … to sing ole ole over that would be like singing fly eagles fly during the Star spangled banner."
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"Hate it when the opposition sing during the #haka," said another. "Totally ruins the atmosphere of it for me."
Many others added similar sentiments.
Others said it was a fair way to respond to the All Blacks' challenge.
The All Blacks performed a revamped kapa o pango haka, led by captain Kieran Read for the first time alongside usual haka leader TJ Perenara.
All Black first-five Richie Mo'unga suggested after the game that it was a symbol of team's togetherness.
"It was awesome. It was very uplifting as a player," Mo'unga said. "I really respect and admire what [Read] did there as a leader, to do something different.
"He stepped out of his comfort zone and really showed the boys he is willing to lead and do something for us on such a big occasion.
"I was fizzed. If you have a captain like that, you follow them."