Manchester City have written to Hampshire police to demand an explanation concerning allegations that Joey Barton made offensive gestures to Portsmouth fans after last weekend's meeting of the sides at Fratton Park.
One of the force's officers claimed he witnessed the England midfielder make a gesture towards a Pompey fan, but a sceptical City want an explanation of the incident in a bid to clear up the matter.
"An unnamed officer purported to have seen something that clearly did not happen," claimed director of communications Paul Tyrrell.
"We have written to the police asking for an explanation. We hope to get a swift response because we are sure they do not want to put any more time and effort into an investigation that, quite frankly, is going nowhere.
"We would like to think the FA will expedite this so we can put the matter to bed.
"We have spoken to the FA because there is clearly no evidence of Joey conducting himself in anything other than the right and professional way."