United have been linked with Everton's Leighton Baines for most of the summer, although, as yet, it is not believed they have made a bid for the 27-year-old.
Yet Ferguson's transfer policy in recent years does not suggest he would invest quite so much in a back-up to Patrice Evra.
And, ahead of tonight's opening pre-season game against AmaZulu in Durban, it appears that is exactly what the Red Devils boss is looking for following Fabio's loan move to QPR.
"It is an area we're paying attention to," Ferguson said.
"In the last five years Patrice has played an average of 45-50 games, which is phenomenal. I don't know if anybody else has achieved that.
"He's still a fit lad. He is a fighter and has the same drive and ambition.
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"But because he is never injured the opportunities haven't been there for Fabio, who needs to play because he has enormous ability.
"With him at QPR for a year, we are a little bit short in that department."
Republic of Ireland Under-21 international Robbie Brady will be given first chance to impress, while England Under-19 star Tyler Blackett could also be involved at some stage.
Yet Evra is fancied to be the man in possession by the time United open their Premier League campaign against Everton at Goodison Park.
After losing the title to Manchester City in such agonising fashion, Ferguson wants it back.
"After the disappointment of last year, we want to recover the title," he said.
"We either win the title or come second - it's an important part of the history of our club over the last 20 years.
"We have to recover, as we've done many times.
"That's our target this year. Priority number one is to win the title back."