The Leicester City striker had a good look at Smith on Monday night and he said: "I think Smith is one of the best centre-forwards I've seen for a long time. If he keeps progressing the way he has been doing then everyone will be talking about him as one of the best, without a shadow of a doubt.
"If he keeps performing like he did against us for the rest of the season, then he should be on that plane."
Ferdinand compared Smith with his former Newcastle team mate Alan Shearer.
"You can look at your Thierry Henry's and that, but you've got to remember Smith's been playing in a struggling team all season. and week in, week out, he's putting in performances like that.
"He was everything you want a centre forward to be. He worked hard and got his goal. I came off the field thinking 'our centre-halves know they've been in a game'. As a centre-forward that's what you've got to do."