Wellington - Argentina kept their World Cup hopes alive with a nail-biting 13-12 (halftime 3-6) victory over Scotland thanks to a dramatic late try on Sunday.
In a high-tempo but error-strewn game that came to life in a gripping final quarter, Los Pumas' win means they are now favourites to qualify as Pool B runners-up behind England.
Argentina, who lost their opener to England 13-9 but went on to beat Romania 43-8, now play Georgia in their final match while the Scots will have to conquer the unbeaten English to ensure a spot in the knock-out phase.
Felipe Contepomi kicked two penalties and converted Lucas Gonzalez Amorosino's try for Argentina. Scotland's points came from a Chris Paterson penalty, a Ruaridh Jackson penalty and drop-goal and a second drop-kick from Dan Parks.
Scotland can have only themselves to blame for the narrow loss, with some poor decision-making and gifting too many turnovers to an Argentina side whose midfield defence was marshalled impeccably by Marcelo Bosch.
The match, played in pouring rain, also featured a litany of handling mistakes and the set-piece was a complete lottery.
For the first hour, there were predictable phases of play that featured strings of badly chased box kicks, non-productive pick-and-go's and inaccurate aerial ping-pong.
Paterson and Contepomi both missed early penalties before the latter finally got Los Pumas on the board after 19 turgid minutes of rugby union.
Scotland's best attacking moment of the first period was squandered when flanker Ally Strokosch passed too early in a clear three-on-two down the left wing.
A similar chance was wasted shortly afterwards when John Barclay opted to drive back infield with numbers outside.
With Argentina offering up little in attack, it was Scotland that went into half-time in the lead through two penalties in three minutes from Paterson and Jackson, the latter a beauty from 47 metres.
Bosch horribly skewed a drop-goal early in the second-half as Argentina tried to turn on the pressure, but the Scots went closest to a try.
Winger Max Evans, a livewire for Scotland, did well to collect his chip into the Argentinian 22m area but was well tackled by Rodriguez before off-loading to Barclay.
From the ensuing ruck, captain Rory Lawson eschewed an overlap on the openside to play the blind and found a wall of beefy Argentinian forwards, who promptly stripped him of the ball.
Paterson had a clear chance to extend Scotland's lead with a drop-goal, but the country's most capped player snatched at his effort and it went wide.
An infringement at a ruck and it was Contepomi's turn, the Pumas captain's penalty effort also drifting wide.
Contepomi made no mistake in the 63rd minute, however, nailing his second penalty after the Scottish front-row collapsed to draw the scores level at 6-6.
That lasted for only a minute as Jackson slotted over a well-taken drop-goal, as Contepomi's fifth penalty attempt went wide off the upright.
In a nail-biting finish to the error-riddled match, replacement flyhalf Parks bagged a drop-goal with practically his first touch to stretch Scotland out to 12-6.
But some woeful defence down the left wing let Gonzalez skip through four tackles, turning a fairly innocuous attack into a try.
Contepomi showed nerves of steel to bag the conversion and take Argentina into a 13-12 lead.
Parks's snatched left-footed drop-goal with a minute to play went wide, leaving Argentina in the driving seat for qualification.