Boston backing Aerosmith in '76. Boston was as tight as a Quad diaphram, then Aerosmith came out and were as 'incoherent' as a turntable being spun by hand. Of course the effects of intoxicating substanced will do that - a common affliction at the time.
'they blew'em off the stage'
what concerts have you attended, where the warm up act blew the headliners away.....my examples...brownville station upstaging zz top to the point where people where chanting 'brownsville station!' during the littl ol' band from texas' set.....another..t.rex upstaging lynyrd skynyrd(yes there really was such a show), and the grass roots upstaging cream.