In spite of her bulky frame, she looks alarmingly frail now, and she spent the evening in a chair, lyric sheets spread out before her. Yet the voice still rings true. One of the titans of Latin American music, Mercedes Sosa, a pioneer of nueva canción – a movement that combines traditional melodies, politics and splashes of Anglo-American pop – delivered a magisterial performance in the smaller venue that sits inside the soulless former Millennium Dome.

Given her age (she’s in her early seventies), her precarious health and the fact that her visits to London have tended to be few and far between, it is likely that we were witnessing her farewell to this country. She could hardly have bowed out more impressively. This was a more focused and consistent display than her last South Bank concert in June. If her voice veers towards the histrionic, few singers can compete with her in terms of majesty.

Like Brazil’s Gilberto Gil, Sosa has come to embody her country’s social and cultural aspirations. She too has managed to outlive a military dictatorship that once forced her into exile. Moreover, she has kept abreast of musical fashions, her compact band slipping elegantly back and forth between acoustic folk melodies, tango and polished soft rock.

Her version of Violetta Parra’s anthem Gracias a la Vida prompted some of the stormiest applause, but it’s a testament to Sosa’s enduring creativity that the material from her recent album, Corazón Libre, proved every bit as inspiring. She may have been sitting down for Sólo pa’ bailarla, yet the sprightly dance rhythms lit up the room.

Sosa detoured into bossa nova on a suitably pensive reading of the classic Insensatez. At the end, as emotions flowed even more freely, she rose and briefly danced a jig as the musicians galloped through Maria Maria.

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