Wilcox only left Manchester City for Saints last summer but comes highly recommended by United's recently-appointed chief executive Omar Berrada.
United are looking for a recruitment expert to work under Dan Ashworth, who is Ratcliffe's top target to become his new sporting director.
Manchester City were keen to keep hold of Wilcox but a late offer to entice him to remain at the club was rebuffed by the 52-year-old.
Wilcox is credited with helping develop rising stars such as Phil Foden, Rico Lewis and Chelsea's Cole Palmer during his six years as director.
A Premier League champion with Blackburn in 1995, Wilcox would provide United with another smart appointment if indeed it goes ahead.
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The Red Devil's have sealed the acquisition of Omar Berrada from Manchester City as chief executive, and will arrive at the end of the season.
Meanwhile, Ashworth is firmly on United's radar after successful stints at Brighton and Newcastle.
But club chiefs are happy to wait for Ashworth's arrival rather than payout a large compensation fee meaning Wilcox could land at Old Trafford before he does.
United's structural shake-up comes after Ratcliffe's deal to acquire a 25 percent stake in the club.
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