American versus British question
A sentence such as, “The Liverpool Philharmonic Orchestra entertained a crowd of over 500 Saturday evening,” makes perfect grammatical sense in American English, and the construction is commonplace in newspapers. An alternative would be: “...crowd of over 500 on Saturday evening.” (addition of “on”)
Since I am British-Canadian, and am doing copy for local press now, I have to be careful to use British English consistently, and I am unsure whether the former construction is standard British English. Certainly the latter is.