Joni Mitchell has performed at the Grammy Awards for the first time

The 'Big Yellow Taxi' hitmaker remained seated throughout her moving performance of the classic folk track.

Brandi had introduced Joni to the stage and celebrated her friend as one of the "most influential and emotionally generous creators in human history".

She said: "Whether we know it or not, any one of us out here who ever dreamed of becoming a truly self-revealing singer-songwriter did it standing on the shoulders of one Joni Mitchell.

"Joni is one of the most influential and emotionally generous creators in human history. She redefined the very purpose of a song to reflect the contents of a person's soul.

"Before she took this leap, the popular song was observational... But the exhilarating risk that we all now take by turning ourselves inside out for all the world to see, started, as far as I can tell, with Joni Mitchell doing it first.

"She's like the first person to strip down at a skinny dipping party, to take that awkward terrifying leap - before everyone else joyfully follows."

The 42-year-old star went on to highlight how Joni has overcome a number of serious health issues over the last few years.

She continued: "In some ways, she didn't have a choice but to take these leaps. She was too preoccupied with basic survival. Surviving poverty, polio, and, as of 10 years ago, a near-fatal brain aneurysm, she didn't dwell too much on how her art was received because she was too busy re-learning to speak let alone sing.

"She's learned to walk three times. Joni just turned 80, my friends! But we all know she's timeless.

"If we are so lucky that history remembers any of us, one thing I know for sure is that it will remember that we lived in the time of Joni Mitchell.

"Today she just won the Grammy for best folk album... Please welcome the matriarch of imagination, a true renaissance woman, my hero and yours, Joni Mitchell."