Giggs, 38, may record the milestone during United's last 32 Europa League clash against Ajax at Old Trafford on Thursday. Ferguson, who signed the Welshman as a schoolboy 24 years ago, insists Giggs has improved with age and sees no sign of him slowing down after recently signing a one-year contract extension.
"It is my personal view, and not everyone will agree with me because we all have our favourites, that even if you take away the longevity, being in the Premier League for as long as he has, achieving what he has; no other player will do it," Ferguson said.
"His use of the ball has got better with age. Changing his position to play in a more central area has given a different aspect to his game.
"We always remember what Ryan was famous for, going up and down that touchline, running at full-backs with great balance and speed. Today it is a different Ryan Giggs. He still has that change of pace and a wonderful balance but he is not as quick as he was 10 years ago and has looked at his game a different way."
Giggs' achievement comes nearly four years after moving past Sir Bobby Charlton's appearance record for United in the 2008 Champions League final, and Ferguson revealed he has been surprised by the level of play maintained by his charge.
"It is amazing really," said Ferguson. "If you go back to Moscow, you are talking almost another 150 games further on.
"He keeps defying age. This season he has just been the same as he was back in Moscow. There is nothing changed from his performance level then as it is today."