Scotland surrendered a 15-point lead as Argentina fought back to seal a series-clinching win in Santiago del Estero.

But Emiliano Boffelli added to earlier scores by Santiago Carreras, Nahuel Tetaz Chaparro and Gonzalo Bertranou to give the Pumas a 34-31 win.

Michael Cheika's side had won the first Test before Gregor Townsend's Scots bounced back with victory last weekend.

Boffelli fluffed a catch from Matias Moroni's offload in Argentina's promising early advance.

Ali Price was called offside, giving the Pumas the first penalty, and Boffelli kicked well.

Scotland's response was impressive as Blair Kinghorn offloaded to Van der Merwe to cross. Kinghorn converted.

But Argentina then got over the line after a wayward Scottish kick through, with Carreras diving over.

The lead quickly changed hands again with the Scots mauling their way through and Ewan Ashman applying the finish, Kinghorn converting again.

A long-range Boffelli penalty was missed but the fly-half got his next one to get his side back to within a point. Kinghorn suffered his first miss with a penalty to keep it tight at the interval.

Scotland got their third try early in the second period with Ashman showing style and grace to evade the chasing Pumas and touch down in the left corner. Kinghorn got back on track with the conversion.

Townsend's side now had daylight and the gap widened soon after with Van der Merwe's second try, the wing leaping under the posts after a series of carries by his forwards to set up an easy conversion for Kinghorn.

Argentina knew they had to register the next try and substitute prop Chaparro provided it, forcing his way over near the line, Boffelli converting.

Kinghorn's first successful penalty gave Scotland more comfort but another poor restart led to Gonzalo Bertranou sniping over. Boffelli's conversion brought the Pumas back to within four.

The Scots then decided to send a kickable penalty to the corner and Argentina seized the initiative.

A scrum near the line led to the decisive moment and Edinburgh's Boffelli went over on the left before adding the conversion.

Argentina: Mallia, Delguy, Orlando, Moroni, Boffelli, S Carreras, Velez, Gallo, Creevy, Sclavi, Petti, Lavanini, Matera, Grondona, Isa.

Replacements: Cinti Luna for Delguy (49), Bertranou for Velez (62), Tetaz Chaparro for Gallo (50), Ruiz for Creevy (50), Gomez Kodela for Sclavi (50), Kremer for Lavanini (49), Gonzalez for Isa (68). Not Used: Albornoz.

Scotland: Smith, McLean, Bennett, Tuipulotu, Van der Merwe, Kinghorn, Price, Sutherland, Ashman, Z Fagerson, Cummings, Gray, Darge, Watson, M Fagerson.

Replacements: Thompson for Smith (75), Schoeman for Sutherland (53), Cherry for Ashman (53), Young for Cummings (69), Christie for Watson (75). Not Used: Sebastian, Horne, Johnson.