Scrum-half Ben Youngs spared England a stunning World Cup defeat as his try pipped Argentina in Dunedin.
Martin Johnson's side were 9-3 down with 13 minutes left when the replacement scooted under the posts.
Jonny Wilkinson, who missed five kicks, including four in a row, converted to put England in front.
He added a late penalty, while Argentina missed six kicks as they failed to punish England's indiscipline.
It was a worryingly poor display from Johnson's men as they gave away eight penalties in the first half and should have been out of the game.
But the radar of Felipe Contepomi, who landed an early penalty but then missed his second, and then Martin Rodriguez was amiss and the Pumas only led 6-3 at the interval.
Rodriguez, who missed five penalties in all, increased the lead to 9-3 four minutes into the second half as it looked as if Argentina might hold on.
But England belatedly managed to generate some quick ball and Youngs sniped over, Wilkinson converting and adding a penalty six minutes from time to give his side a narrow victory.
The game was played in the new Otago Stadium, the world's first fully-enclosed grass arena, which created a tremendous atmosphere, with England and Argentina fans split roughly 50-50.
“England looked very unconvincing for the vast majority of the game but one magic moment from Ben Youngs turned the result in England's favour. It was probably Wilkinson's worst ever kicking performance for England ”
Ian RobertsonBBC 5 live rugby correspondent
Argentina, as expected, came charging out of the traps, swarming their England counterparts at the breakdown and very nearly scoring after four minutes, but Julio Farias Cabello's extravagant dive for the try-line was in vain.
Contepomi, however, slotted the resulting penalty from bang in front of the posts before Andrew Sheridan strayed offside at a ruck, only for full-back Rodriguez to miss the three-pointer from long-range.
England struggled to make any impact on the game in the opening 10 minutes, and when they did gain possession Pumas defenders were there in force, putting in some muscular hits.
Wilkinson squared things up after Rodrigo Roncero went high on Ben Foden but the infringements continued to flow from England and they were lucky the Argentine goal-kickers were in profligate mood.
Rodriguez missed another long-range effort after James Haskell was penalised for not rolling away before Contepomi tugged an effort right of the posts, although Rodriguez did give his side the lead after England tight-head Dan Cole went off his feet at a ruck.
Ben Dirs' Blog
“Johnson does not have long to work the magic, and there is very little evidence to suggest he is inclined to change tack in the middle of a World Cup”
Foden made the only clean line-break of the first half for England and found Delon Armitage on the left wing with a long pass. Armitage fed Tom Croft but the Pumas scrambled back to concede a penalty, which went unpunished as England kicked for touch rather than goal.
Cole was shown a yellow card on 34 minutes for repeated England infringements only for Rodriguez to miss again, but the Pumas nearly took advantage on the stroke of half-time, fleet-footed Exeter winger Gonzalo Camacho sashaying through the England defence before veteran hooker Mario Ledesma was sent flying into touch.
If England manager Johnson's half-time team-talk was full of fire and brimstone, then it did not have the desired effect. First, Rodriguez opened up the England defence and then Marcelo Bosch, on for the injured Contepomi, waltzed through a gaping gap left by Nick Easter and Chris Ashton, who ushered him through.
Rodriguez increased Argentina's lead to six points after 44 minutes as England's penalty count continued to mount before he and Wilkinson exchanged failed penalty attempts.
Youngs replaced Richard Wigglesworth with 30 minutes remaining, but the appearance of the Leicester scrum-half did nothing to settle his half-back partner, with Wilkinson missing his third penalty, from the left touch-line.
3 out of 9
2 out of 7
Tackles made (missed)
Time in opp. 22
Rodriguez then contrived to miss his fifth three-pointer before, remarkably, Wilkinson failed with a fourth as the game descended into an ill-disciplined mess. But when Camacho was whistled for a dangerous tackle on Foden, Wilkinson kicked for the corner and from the resulting line-out, Youngs darted over for his second Test try.
Wilkinson kicked the conversion from in front of the posts to give England a one-point lead and increased that by three courtesy of a penalty with six minutes remaining.
The ageing Pumas pack began to fade as the clock ticked down and, one by one, their old warhorses were replaced. However, their fire had not been entirely extinguished, and England had to be alive to a couple of late thrusts.
While Johnson will no doubt be relieved at the win, the disjointed, ill-disciplined and guileless nature of the performance leaves him with plenty to ponder and gives future Pool B opponents, including Scotland, plenty of hope.
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