I was there too. I think it was an idea of Dragan Lukic's, to invite top flight teams to play friendlies and boost the finances, as the regular crowds were too small. (Actually thinking of the year maybe it was Freddie Pye's idea?)
It was quite generous of the clubs to do this, and from what I remember they sent strong teams; I remember Peter Barnes was certainly playing for City, I have a mental image of him towering over Johnny Price.
About a month later we played Stoke City (then a top flight team) by which time we had George Best playing in our side.