It's really wonderful to see Leon Russell get some much-deserved attention because of his collaboration with Elton John. Hearing Russell's still-vital voice on "The Union" caused me to dig out his early solo albums.
And here's a little trivia: Which of Russell's greatest songs did he never record on one of his own albums? That would be "Superstar," the most popular version of which was recorded by The Carpenters. Russell actually co-wrote the song with Bonnie Bramlett, who with her then-husband, Delaney, fronted a much-admired blue-eyed R&B band in the late '60s and early '70s.
Russell played on their albums, the second of which--"D&B Together"--featured "Superstar." (Actually titled on the album as "Groupie [Superstar].") The song was performed by Rita Coolidge on the "Mad Dogs & Englishmen" tour and album, and I had the fortune of hearing Russell perform it live on his own tours in the early '70s. Here's the first recorded version, from 1972.
Download 10 Groupie (Superstar)