Adam Jones was injured in the second half of the 28-25 defeat in Pretoria
Wales' Adam Jones is set to be sidelined for six months and will have surgery on torn shoulder ligaments.
The British & Irish Lions prop suffered a dislocated shoulder in the second Test defeat by South Africa following a dangerous charge by Bakkies Botha.
Ospreys Physio Chris Towers revealed: "Adam had a scan which confirmed that he had torn ligaments in the shoulder in the process of the dislocation."
It means a potential prop crisis for both Wales and the Ospreys.
Jones enhanced his scrummage reputation after his performance against Springbok prop Tendai "The Beast" Mtawarira.
But was injured after a collision with Botha and the South African missed Saturday's final Test defeat to the Lions in Johannesburg after being banned for two weeks for his dangerous charge on Jones.
Jones was just one of a host of Lions injuries in a bruising second Test and returned home on Wednesday for the Ospreys medical team to fully assess his condition.
Towers added: "In light of thee findings, Adam then saw a specialist who has recommended that the best management of the injury is to undergo surgery to repair the ligament damage.
"We would expect excellent results from the surgery, however, we are looking at a timescale of around six months before Adam would be able to play rugby again."
Fellow Wales prop Gethin Jenkins was injured in a clash of heads with Springboks winger Bryan Habana and with Jones leaving the field at the same time, it forced the introduction of uncontested scrums.
Centres Brian O'Driscoll (concussion) and Jamie Roberts (wrist) were also ruled out of the third Test.
Jones has returned home and after being assessed will be operated on next week.
Wales take on New Zealand, Australia and Argentina in November but Warren Gatland's team have limited options as tighthead prop back-up.
John Yapp, a loosehead by trade, started both wins against Canada and USA last month at tighthead.
Coach Gatland also has the likes of Craig Mitchell, Eifion Lewis-Roberts and Rhys Thomas at his disposal but Wales will be without Chris Horsman has been forced to retire with a neck injury.
Jones' injury is also a blow for the Ospreys' Heineken Cup ambitions. He will miss the regions first four matches of their pool, which includes Clermont Auvergne, Leicester and Viadana.