At that point Scotland, through drop goals to Ruaridh Jackson and Dan Parks, had their foot on the throat and were controlling the game played in dreadful conditions, but relented.
They still had a chance to win it at the death but Parks was forced to hurry a left-foot snap in front of the posts and he was charged down by Argentina captain Felipe Contepomi. Seventy minutes of dire fare had suddenly spawned a gripping final 10 minutes.
"Tactically we were very smart," said Robinson. "We controlled the opposition, but 30 seconds of madness really cost us."
That 30 secs saw Scotland concede a penalty and then let Amorosino to outflank them, scoring a try from nothing. Contepomi, who had not enjoyed a great night with the boot, showed that great players live for the moment by slotting an angled conversion.
"He is probably right," he graciously said of Robinson's assertion that Scotland had dominated the match. "They were better than us, but rugby is played for 80 minutes."
Scotland now head to Eden Park to play England in a match they have to win well to have any chance of reaching the knockout stages. That would appear to be a long shot.
Last night, Jackson looked as if he had provided the game's decisive moment when he landed a drop-goal that broke a 6-6 stalemate with 15 minutes to go, but injury-hit Argentina grabbed a late lead and held on.
After the All Blacks' impressive victory over France at Eden Park, speculation increased as to who they would rather meet in the October 9 quarter-final, Argentina or Scotland, assuming England would top the Pool B.
On last night's evidence, Argentina should not hold too many fears for the men in black, particularly with injury clouds hanging over forwards Juan Martin Fernandez Lobbe and Rodrigo Roncero, who both left the field.
Lobbe's injury is thought to be ligament related, so he could face an extended spell on the sideline.
There is no great mystery to the way Los Pumas play. They ally a destructive tight five to an athletic loose trio to slow the tempo at the breakdown. It requires a physical commitment that borders on the insane.
When they're not quite on the edge and lose the battle for the gain-line, which they for much of last night's match, they can look a little ponderous.
As for their backs, they are reduced to kick-chasers, even with the artful Felipe Contepomi restored to health.
It is a fraught tactic against clever counter-attacking sides, of which Scotland are not. It can also make for some turgid fare.
Unless you're a fan of futile long-range penalty attempts and scuffed drop-kicks there was not a lot to quicken the pulse in the first half, or much of the second for that matter.
First five-eighth Santiago Fernandez popped over a clever chip-and-regather which led to a penalty in front of the sticks and the first points of the game in the 18th minute, but that was your lot.
Clinging to a narrow lead against a team that usually gives them trouble, the last thing Argentina wanted to see was their inspirational No 8 Lobbe leaving the field. His departure coincided with a sustained period of Scottish pressure. That was finally turned into three points when Wayne Barnes awarded Scotland a scrum penalty on Pumas' ball.
Chris Paterson nailed that and doubled his tally with a long-range shot just before halftime.
Completely unmemorable stuff, really, until those frantic final moments.
Argentina: 13 (Lucas Gonzalez Amorosino try; Felipe Contepomi 2 pen con).
Scotland: 12 (Chris Paterson 2 pen Ruaridh Jackson dg Dan Parks dg).
Half-time: 3-6.
