Scotland let a 21-point lead slip to lose 33-24 to Argentina in a gripping clash at Murrayfield.
The Scots led 14-0 at half time and scored a try not long after the restart, but the Pumas roared back in extraordinary circumstances - with Scotland booed off at the end by some fans.
It was another dispiriting defeat for Scotland, a week on from running New Zealand close in Edinburgh.
Scotland started the match well and quickly established their superiority. They opened the scoring on 13 minutes when Jack Dempsey was sent clear by Finn Russell and he powered over the tryline, with the stand-off adding the extras.
Argentina could not find a way through a well-drilled Scottish defence and the hosts cashed in again on 28 minutes. Jamie Dobie teed up Ewan Ashman and the hooker burrowed and twisted his way over, with Russell again converting as Scotland went in 14-0 up at the break.
Scotland extended their lead four minutes into the second period when Dobie fed Ashman once more and he charged over. Russell maintained his flawless kicking display to make it 21-0.
Argentina got a toehold in the match on 57 minutes when captain Julian Montoya landed a try after review, with Santiago Carreras converting for 21-7. Scotland had gone down to 14 men moments earlier when Blair Kinghorn was cautioned for repeated Scottish infringements.
That sparked Argentina into life and they scored again on 60 minutes through winger Rodrigo Isco. This time Carreras could not convert and it was 21-12.
Russell landed a long-range penalty to make it 24-12 on 64 minutes and Scotland had a bit more daylight to play with.
It was required. Argentina kept going and landed another try, this time under the posts, from Pedro Rubiolo. Carreras converted and suddenly the Scottish advantage was only 24-19.
Argentina now had all the momentum and scored again on 75 minutes as Pablo Matera crashed over under the posts and Carreras kicked the conversion to put the Pumas 26-24 ahead.
Argentina weren’t letting go and they completed an incredible comeback when Justo Piccardo tore away to score. Carreras landed the kick and the game was done.
5. Grant Gilchrist
Disrupted one lineout and like many of the forwards just could not withstand a second-half barrage. Limped off towards the end. 5 | SNS Group / SRU
6. Gregor Brown
The back-row's afternoon only lasted eight minutes after he failed an HIA early on. Replaced by Fagerson. n/a | SNS Group / SRU
7. Rory Darge
Lucky to avoid a yellow card after a high hit on Grondona at start of second half. Limited impact as the game wore on. 5 | SNS Group / SRU
8. Jack Dempsey
Opened the scoring on 13 minutes - his second try for Scotland - when he burst on to a Dobie pass. Some good carries but tested defensively. 6 | SNS Group / SRU