Martin was Unitedâ€™s chief scout and recommended the former Porto midfielderâ€™s signing.
Ferguson recalls: "I sent Martin to watch him in every game for four or five weeks.
"Martin said: 'Alex, heâ€™s better than Rooney.'
"'For Christâ€™s sake, donâ€™t say that,' I told him. 'Heâ€™ll need to be good to be better than Rooney.'
"Martin was adamant."