Argentina No. 8 Leonardo Senatore was cited Sunday for allegedly biting South Africa lock Eben Etzebeth during a Rugby Championship match in Mendoza on Saturday.
Etzebeth told Australia-based referee Steve Walsh he had been bitten on the arm during a Test won 22-17 by the Springboks, but the television match official found no evidence.
However, a post-match review of the mid-second half incident by the citing commissioner led Championship organisers SANZAR to issue a statement.
"Senatore allegedly bit South African player Eben Etzebeth. The incident occurred in the 61st minute of the match at Estadio Malvinas Argentinas.
"Upon further review of the match footage the citing commissioner deemed in his opinion the incident had met the red card threshold for foul play."
The statement did not say when the hearing would be held. The International Rugby Board ban for biting ranges between 12 weeks and four years.
England-based Senatore was yellow carded in South Africa a week ago for a high, dangerous tackle in a first round match lost 73-13 by the Pumas.
Flanker Francois Louw was another furious South African forward in Mendoza, telling the referee he was the victim of an eye gouge by Pumas loose forward Pablo Matera.
But a review of the incident by Irish television match official Marshall Kilgore found no evidence to back the claim as a fiery second half unfolded.
After a nine-try romp in Soweto, South Africa battled to subdue vastly improved Argentina and took the lead for the first time just eight minutes from time.
There was no sign of the running Springboks rugby of last weekend and they were indebted to fly-half Morne Steyn, who slotted five penalties and a conversion for a 100 percent record.
An Argentine side lacking key forwards Juan Martin Fernandez Lobbe and Patrico Albacete through injuries outscored South Africa by two tries to one only to be let down by ill discipline.
A couple of collapsed mauls in the closing stages presented the rattled visitors with two penalties and ice-cool Steyn kicked both to keep South Africa top of the table.
Defending champions New Zealand, who completed a double over Australia with a 27-16 win in Wellington, also have nine points, but an inferior points difference.
"We were not good enough," admitted South Africa coach Heyneke Meyer after seeing his spluttering side make it eight wins on the trot, including four on the road.
"However, there are some positives to take from the game -- we prevented Argentina scoring during the second half and we improved as the game wore on.
"Sometimes you get plenty of quick ball and score lots of tries and sometimes you have to grind out a victory," said the coach tasked with winning the 2015 Rugby World Cup.
Argentina coach Santiago Phelan was cheered by the performance at a ground where they were unlucky not to get more than a 16-16 draw against South Africa last season.
"We worked hard on the mentality of the players during the build-up and the results were evident -- a much improved performance from a highly committed team.
"Unfortunately, we could not win, but every Argentine player can be proud of his performance. I could not have asked for more from them."
After a one-week break, the southern hemisphere championship resumes on September 7 with New Zealand hosting Argentina and Australia at home to South Africa.