Abomb did mention that it was the original version of "Layla".....
Also, Duane Allman played lead-guitar along-side Clapton.... The only element that somewhat ruined the song was Derek & the Dominos drummer's, Jim Gordons, piano solo that got tacked on at the end....
Legend has it.... Layla was George Harrison's first wife, Pattie,
and Derek was a pseudonym for Clapton himself.... At that time, he was having an affair w/Pattie Harrison..... Harrison was EC's best friend at the time... Clapton wanted to write a song conveying his love towards Pattie, and figured that it would work by concealing their true identities.....
Another awesome song from their album is "Bell Bottom Blues", which I even consider better than "Layla"....