South Africa director of rugby Rassie Erasmus will face a misconduct hearing after his criticism of the match officials following their first-Test defeat by the British and Irish Lions.
World Rugby said the "extensive and direct nature" of Erasmus' hour-long video monologue is a potential breach of the Code of Conduct.
In a statement, it called officials the "backbone" of the sport.
"Without them there is no game," it said.
"World Rugby condemns any public criticism of their selection, performance or integrity which undermines their role, the well-established and trust-based coach-officials feedback process, and more importantly, the values that are at the heart of the sport."
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Erasmus spoke for 62 minutes, direct to camera, and in particular highlighted the performance of Australian referee Nic Berry in the match the tourists won 22-17.
He felt South Africa players - including captain Siya Kolisi - were not held in the same regard as the Lions and their skipper Alun Wyn Jones.
In the video posted on Vimeo, Erasmus said: "Let the Springboks and the Lions have an equal chance on the field when it comes to laws, respect, the way players are treated, what is said in the coaches' pre-match meeting with the referees, how they give feedback post-match and how things are said in the media.
"It's comical the respect the [officials] showed towards the South African players compared to the Lions players."
The World Rugby statement said it had reminded both sides of their obligation to uphold the integrity of the sport.
"It is an opportunity for both teams and their management to set a positive example and concentrate on the spectacle and a wonderful example of rugby and its values at their best," it added.
South Africa drew level in the series with an emphatic 27-9 win in the second Test in Cape Town last weekend.
The series decider takes place in Cape Town on Saturday at 17:00 BST.
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