The 28-year-old began his career with the Old Trafford outfit but, faced with competition from Andy Cole, Dwight Yorke, Ole Gunnar Solskjaer and Teddy Sheringham, it is perhaps no surprise he made just a single league appearance before joining Preston in a £1.5million deal.
Healy enjoyed a productive spell at Deepdale and then spent three years at Leeds before Lawrie Sanchez offered him a Premier League chance this summer.
But it is with Northern Ireland that Healy has made the biggest impression, scoring a record 13 goals during the Euro 2008 qualifying tournament.
"David has been fantastic," said Ferguson. "When he was here as a young lad, David was blocked from making progress simply because at the time, we had four top strikers.
"We got a very good offer from Preston, which let the boy get on with his career and his form for Northern Ireland has been amazing.
"To score 13 goals from a country which is nowhere near one of the top sides in Europe is absolutely brilliant."