A shaky start for the star’s 90th birthday celebration made this concert more than a metaphor for the transformative power of music.

There aren’t many 91-year-old musicians who can pack out the Barbican to capacity, but then again there aren’t many still making music. Ravi Shankar is no ordinary performer. A star of classical Indian music, he famously collaborated with George Harrison and popularised Indian music in the West. Shankar’s performance on Tuesday defied many odds, not just age and ill-health.

His appearance 40 minutes into the concert was greeted with a standing ovation. The frail musician, who was helped on-stage, had visibly aged since his ‘farewell’ performance here in 2008.

He got off to a shaky start as he wrestled with the sitar - each pluck seeming like a monumental effort. But after a painful 15 minutes, he began playing with ease as the energy of the music appeared to carry him.

His 90-minute set included four ragas and a performance of Rabindranath Tagore’s poem Don’t Forget Me.

The last raga was easily the best; wild, free and played with abandon. It included an experimental arrangement that felt more rock than classical, and brought back memories of Shankar in his heyday.

After being led off-stage, once again to a standing ovation, he popped his head back through the curtains like a mischievous child.

Age might have diminished his body, but clearly not his spirit. Although Shankar has defied the odds to perform again in London after his farewell tour, this sadly felt like the end of an era.