Paralympic hero Tanni Grey-Thompson has been turned down for a key role in delivering London 2012's legacy amid claims of a Government 'stitch-up'. A political row is expected to spark today when ministers announce that the new head of Sport England will be Nick Bitel, chief executive of the London Marathon. It is claimed Baroness Grey-Thompson, who had the backing of Lord Coe and was Mr Bitel's main rival, was overlooked because she had been too critical of the Government. Although the 43-year-old who won 11 Paralympic gold medals sits in the Lords crossbench peer, she has lead criticism of disability benefit cuts. Hugh Robertson, the Sports Minister, will say today that Mr Bitel, who has been in charge of the London Marathon since 1995, was the best candidate for the job, The Times reported. Whitehall sources told the paper: 'In terms of national organisation, leadership, commercial experience, he's got it all.' It was Lady Grey-Thompson's lack of exp