Ferguson told the FA that Giggs was United's only over-23 player they could pick for the Olympics and Stuart Pearce selected the midfielder ahead of former Old Trafford hero David Beckham.
"Sir Alex played a big part in my participation," Giggs told the Sunday Mirror. "Right from the start, he was keen for me to be involved and he's backed me ever since really.
"He's been good and he recognises that maybe a tournament could add to what already is a pretty good career.
"He's been supportive all the way through my career, since I was 13 through to today."