Etzebeth, the most capped Springbok player of all time, received a permanent red card in his side’s 73-0 thumping of Wales in Cardiff last Saturday, with condemnation coming from all quarters and his own coach Rassie Erasmus admitting "it did not look good".
The two players tussled late in the game among a melee, and Etzebeth was seen to make contact with Mann's eye with his hand, but said he was acting in self-defence.
"I did not, at any stage, aim for his eyes or intend to make contact with his eye," Etzebeth was quoted as saying in the judgement released by the independent disciplinary committee.
The committee, chaired by Christopher Quinlan KC and also including former England internationals Leon Lloyd and Becky Essex, believed the action was intentional though and warranted a mid-range entry point of 18 matches on the offences scale.
This was reduced by six matches due to the player’s disciplinary record and "some mitigating factors", according to the panel.
New Zealand flanker Ardie Sevea provided a character testimonial in support of Etzebeth, while Mann did not take part in the hearings at all.
Etzebeth will miss the next 12 games for his Durban-based United Rugby Championship franchise the Sharks, and will be available again from April.
He will not miss any matches for the Springboks, who are not in action again until July.