Clapton didn't play the Les Paul that much, and in August 1968 he gave it to his good friend George Harrison, who promptly named the guitar "Lucy," in honor of redheaded TV star Lucille Ball.
Harrison and The Beatles were at the time recording what would become "The White Album." Unable to track a lead solo he was happy with for his song While My Guitar Gently Weeps, Harrison called Clapton up and invited him to play on the cut, telling him "you don't need to bring a guitar; you know I've got a good Les Paul you can use." Clapton laid down his searing solo in one take.
Harrison became enamored of Lucy, and used the guitar for several years. In 1973, he loaned it back to Clapton for Eric's Rainbow Concert.