Several high-profile rugby commentators have had their say on the incident, including Welsh rugby pundit Jonathan Davies and the Telegraph's Mick Cleary, respectively labelling the ruling "clueless" and "ridiculous".
"Concussion is the sport's gravest issue," tweeted Cleary.
"Governing bodies claim to recognise that disturbing fact/trend. And then let this slip by as if it were a routine incident."
Cleary later followed up on his tweet to explain that he believes the ruling was not as a result of favourable treatment from World Rugby towards the All Blacks.
World Rugby explained how the incident didn't meet their standard of a red card.
"Having reviewed all available camera angles, the Citing Commissioner considered Ofa Tuungafasi to have executed a dangerous tackle "just short of" red card level (in accordance with World Rugby Regulation 17), which caused injury to France winger Remy Grosso," a World Rugby statement said.
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"In considering the mechanics of the incident, the Citing Commissioner determined that there were mitigating factors which prevented the conduct from reaching the red card level in his opinion. These included Remy Grosso's body position lowering as he went into contact with Sam Cane, who effected the tackle initially, immediately before Ofa Tuungafasi joined a dynamic tackle situation.
"As a result, the independent Citing Commissioner issued a Citing Commissioner Warning – issued for acts of foul play that are viewed by the Citing Commissioner to come close to but do not warrant the player receiving a red card."
The Citing Commissioner also said that Cane's initial high tackle on Grosso was worthy of a penalty and no further punishment.
Tuungafasi apologised to the Frenchman after the test, stating it was unintentional.
"Remy, I hope you're recovering well. It was a physical game and it wasn't my intention to hurt you," he wrote on Twitter.
"I'm also gutted that I didn't get to see u after the game and u weren't well for me to visit u in hospital this morning before we left but I hope to catch up soon brother (sic)."
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