There was a time when even the Emperor Hadrian wouldn't have bothered trying to build a wall as tight as the South African rugby defence.
Former Springbok coach Jake White built his entire strategy around a watertight rearguard, one so structured and organised it was able to repel almost all attackers for hours on end.
But today, that defensive wall lies as abandoned, as broken as the old pile of bricks on the England/Scotland border.
So when the dust settled on one of the greatest test matches the game had ever seen in Bloemfontein last weekend, some pertinent questions needed to be asked.
Not whether there was still any spirit left in this defeated Springbok squad who have finished bottom of the 2010 Tri Nations table. That one was answered in bucket loads as the 'Boks turned around a ruinous 6-31 deficit to lead 36-31 with minutes left to play.
Only personal pride and a deep well of belief would drag a team out of that particular pit into a position to win a game.
That they failed to seal the deal, when they were still in front, had possession and were less than 40 seconds from the final whistle, shattered the South Africans.
It was a tragedy for John Smit and his men that they couldn't finish off one of the bravest, most courageous comebacks in the history of test match rugby.
But for all the eulogies regarding South Africa's comeback, there have to be boards of inquiry set up to understand what the hell has happened to the Springboks' defence.
Not just in Bloemfontein, where they sank to that 6-31 plight within the first 25 minutes, but in Pretoria the previous week when Australia led 21-7 after 11 minutes.
In fact, South Africa made disastrous starts to just about every single Tri Nations game this season. If they weren't conceding early tries, they were getting their players sent to the sin-bin in the first few minutes.
Defence was the cornerstone of South Africa's triumph at the 2007 Rugby World Cup. Players in that squad knew down to their fingertips their role, their optimum positions in a structured defensive alignment that few opponents were able to break. In seven matches at that tournament, South Africa conceded just nine tries.
Yet in the last 11 months under this new coaching unit, the Springboks give every impression of defending like naive children. They don't operate as a unit, they don't appear to have a clue as to how to shut down space and isolate the oncoming ball carrier and they continue to miss important tackles.
In this season's Tri-Nations, South Africa conceded 22 tries in six games. Last year, en route to the title, they shipped 11, exactly half. Just what is going on behind those doors they close so tightly in training? No wonder they don't want to let anyone in - if what we see on the field during a game is a decent barometer, then it must be comic capers at training every day.
No one in this entire Tri Nations season has been able to get the Springboks to defend properly and work together. One has to ask why. Who is doing the coaching? Do they know what they're doing? Or is it the players who are culpable? Are they ignoring what they're being told or are they so dim they can't understand the techniques of the task?
You can rule out the latter, surely. If that were the case, they wouldn't have defended so well at the last World Cup.
It is always hard to be critical after such a magnificent game of rugby and so wondrous a comeback. But if these Springboks are to have any hope of retaining their world crown in New Zealand next year, someone is going to have to bite the bullet and demand answers to these questions.
Just being fobbed off, which is what all modern day press conferences are about, will not do. SARU will be deficient in their duty if they don't get to the bottom of this mess.
Both the All Blacks and Wallabies have each cut the Springboks' defence to shreds three times this year.
It is true that some of the tries scored in this year's tournament have been conceived and finished by class attacking play. Sometimes, too, you just have to put up your hands and acknowledge that.
But South Africa's leaky defence has been one of the main causes of their woes. It can't go on like this for, despite their heroics in their last two games, they have finished bottom of the table. But will anyone be asking the hard questions as to why?