On this Day May 20, 1966
Origin of article http://www.thisdayinmusic.com/onthisday.php?factid=16348
Pete Townshend and Roger Daltrey of grew tired of waiting for John Entwistle and to arrive for their gig at the Ricky Tick Club in Windsor, England so they took to the stage with the bass player and drummer of the local band that opened the show. When Moon and Entwistle finally arrived in the middle of the set, a fight broke out, with Townshend hitting Moon on the head with his guitar. Moon and Entwistle quit the band, (and rejoined a week later).