Grant has come to the attention of police after they launched an investigation into a brothel where prostitutes charge £130 for intercourse.
The married father of two, formerly in charge at Chelsea, was pictured by The Sun entering and leaving the building on a shabby industrial estate near his club's training ground, before clambering into a chauffeur-driven car.
Touchline duty: Portsmouth manager Avram Grant (right) dishes out instructions to Hassan Yebda during Pompey's 1-0 defeat at Fulham on Wednesday
Although Grant is said to have freely admitted that heknew it was a brothel, the newspaper was unable to reveal his identitylast year, citing 'creeping privacy laws'.
At the time football fans' websites were flooded withspeculation about his identity, with many accurately naming 54-year-old Grant andhis club within hours of the story breaking.
In recent weeks his name has been widely circulated on theinternet, with more than 10,000 references to the brothel visit onvarious websites.
Avram Grant, pictured with wife Tzofit in 2004, may be questioned by police after he was photographed leaving a 'massage parlour'
His identity has now been revealed by the Daily Telegraph after police sources confirmed that they were pursuing an active investigation into the brothel.
Police told the newspaper that they will be speaking to clients ofthe brothel, any of whom could be called as witnesses if the inquiryresults in a prosecution of anyone alleged to be living off immoralearnings.
Smells like trouble: Portsmouth boss Avram Grant makes his way to the dug-out at Craven Cottage
A source close to the investigation said: 'We want to speak to people who have been there, to clients who might be potential witnesses.'
In recent months there have been a number of cases in which wealthy and famous individuals have successfully used the Human Rights Act to gag the media.
MPs and lawyers have protested against the march of privacy laws, saying they have become an intolerable burden on freedom of speech and are winning Britain an international reputation for censorship and suppression of information.
However, last week's landmark ruling by Mr Justice Tugendhat to revoke a 'super-injunction' granted to England captain John Terry has swung the pendulum back in favour of freedom of speech, say legal experts.
Of the brothel investigation, a spokesman for Hampshire Police said: 'We are aware of certain allegations that have been made in connection with that location.
'There is nothing to evidence the allegations at the moment.'
Israeli-born Grant, who used to manage Chelsea, allegedly declined to answer questions about the brothel visit which were put to him via his solicitor this week.
The brothel is a short drive from Portsmouth's training ground in Eastleigh, Hampshire, and is housed in an industrial unit in the village of Horton Heath.
Grant's trip to the brothel was said to be his second following an hour-long visit in October.
Prostitution is not against the law in the UK, nor is using the services of a prostitute in a private place, but keeping a brothel is illegal under the Sexual Offences Act 2003, and carries a maximum prison sentence of seven years.
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