Argentina celebrated their first home test in almost three years with a close-fought 26-18 victory over Scotland at the Estadio 23 de Agosto on Saturday.
The home side outscored the tourists three tries to two but failed to capitalise on a strong first-half showing, and an 18-6 halftime advantage, as Scotland fought their way back into the contest, only to let it slip.
Jeronimo de la Fuente, Santiago Carreras and Gonzalo Bertranou crossed over for Argentina while Matt Bennett and Rory Hutchinson were Scotland's try scorers in the first of a three-test series.
Nicolas Sanchez kicked over two penalties, before going off early with a muscle tear, with Emiliano Boffelli adding a penalty and conversion for Argentina.
Blair Kinghorn was successful with two penalties and a conversion for Scotland.
Travel restrictions during the COVID-19 pandemic had seen Argentina unable to play at home since losing to South Africa in Salta in 2019 and their return ensured a sellout crowd in the provincial town.
They were treated to a dominant first-half showing as De la Fuente and Carreras, who had come on for Sanchez, both scored from close in.
But Scotland, who failed to enter the opposition's 22-metre area in the first half, suddenly sprung to life after the break as Bennett powered over and Hutchinson added a second try to see the scores level at 18-18.
Parity lasted three minutes before a controversial try from scrumhalf Betranou, drafted into the line-up on the eve of the game when Tomas Cubelli was ruled out, restored Argentina's advantage.
It was dotted down in the corner but did not look to have been properly grounded or have crossed the line. Extensive revision by the Television Match Official proved inconclusive but the try was awarded anyway by referee Nic Berry.
Scotland should have levelled matters but blew a golden chance with a forward pass down the line when centre Sam Johnson looked odds-on to score.
That allowed Argentina to stay ahead and when they were awarded a 71st-minute penalty, Boffelli struck it over to increase the gap to eight.
The result ensured a winning start for new Pumas coach Michael Cheika, the former Australia coach who has replaced Mario Ledesma just over a year before the 2023 World Cup in France.
Argentina host Scotland in Salta in the second Test on Saturday, followed by a third in Santiago del Estero on July 16.