Brown had been struggling with the damaged ankle that forced him off at half-time during the defeat by Samoa last weekend and today became the third player to leave the party early after tighthead prop Geoff Cross and hooker Pat MacArthur were both struck down with injuries.
Now that flanker Brown too is about to head home, it leaves head coach Scott Johnson not only hunting a new leader but also somebody who can fill the openside slot in his team ahead of Saturday's clash with the Springboks.
However, Johnson has moved to make life a little less desperate in the front row, though so stretched are his resources that he has had to call up a player who has never started a professional game and has played only four matches off the bench.
Fraser Brown, who has just signed a contract to join the Glasgow squad for next season, will arrive in South Africa tomorrow as cover for Steve Lawrie, the Edinburgh hooker who made his debut last weekend but is struggling with a niggling back problem.
"It is traditional for all teams to have three hookers," explained team manager Gavin Scott.
"So with Pat leaving there was a reasonable certainty that we would need that coverage. With the short travel time to South Africa we were able to leave it, but with Stevie having a tight back - that is all it is, he could not train yesterday or today but the medics are saying he is a lot better - we had to bring him (Brown) out."
It is a surge into the big time for Brown, a former Under 20 captain but who has struggled with injury since moving into senior rugby.
With Ross Ford, Dougie Hall and MacArthur all injured - as are some of the other journeymen hookers still in Scotland - the team management were running out of options.
The remaining injuries are giving more cause for hope, with Scott confirming prop Euan Murray is making good progress with his hamstring problem, as is Johnnie Beattie with a damaged shoulder. Both are expected to be available for selection at the weekend.
Tom Heathcote and Alex Dunbar are going through the sequence of tests to check they are not concussed, so far without any sign of trouble.
While Brown's loss is a serious blow, it will almost certainly create the space for David Denton to resume his international career after a disastrous season that started with an ankle injury and finished with him sidelined due to knee trouble.
"It would be awesome to play," he said. "It is 14 weeks since I last played and I am gagging at the bit to play in any capacity, all I have asked for is an opportunity to win my place back.
"Every time I felt I have gained momentum I have picked up another niggle. That is very frustrating, something I have never experienced before. Hopefully that is the end of the bad injuries."
Born in Zimbabwe but educated in South Africa, Denton is looking forward to playing in the land where he learned his rugby for the first time since he moved to Scotland.
"I will be one of the freshest guys in the squad, since I have not played," he said.
"South Africa have a simple game plan. They will play a physical game, especially after watching us at the weekend. We cannot let that happen. If we do not front up physically we won't win the game but we have a group of players more than capable of doing that. I am confident we can front up.
"If I am on the park there is no question what my job is. It is to make sure we are in the game physically and they are not bullying us, which happened at the weekend. I love that. That is why I play rugby."