Mr Murphy has recently returned from a trip to Qatar with the International Trade Union Confederation, during which he said he saw evidence of migrant workers being lured to the Gulf state by the promise of good salaries, only to have their passports taken away so they cannot return home. He said it was for the football authorities, rather than Government, to put pressure on the tiny Arab kingdom, which was a surprise choice as host for football's biggest tournament when it was picked by Fifa over the US, South Korea, Japan and Australia in 2010.
Mr Murphy told Sky News's Murnaghan Show: "What I saw there will stick with me for a very long time. Unless Fifa and the football authorities act on workers' rights in Qatar, the game that I love I will be embarrassed by and ashamed by forever.
"The migrant workers working there - who are already building much of the infrastructure, the hotels, railways and roads that will help make the World Cup possible, and are now beginning to build the stadiums - are living and toiling in conditions that are sub-human. They sign on to contracts in countries such as Kenya and Bangladesh, they are promised wages that they couldn't earn at home, but when they get there, their contracts are torn up. Many of them have their passports seized from them by their employers.
"They can't leave the country and this is a dreadful, ugly secret of the most beautiful and democratic game in the world."
Mr Murphy said he had met one Nepalese worker who had been stranded in Qatar as a stateless person for five years because his employer had taken his passport out of the country, leaving him unable to go home.