Mikael Silvestre and Ben Foster also completed 90 minutes each in their ongoing pursuit of match fitness, but it was the Reds’ young guns – and Welbeck in particular – who stole the show.
The Reds had to recover from the concession of an early goal against Manchester City last week, and it was the same story again as Newcastle took the lead after 36 minutes.
James Marwood scuffed his shot completely, foxing the United defence, and Jonathan Godsmark was on hand to hook a 15-yard shot past Foster and into the far corner.
Wesley Ngo Baheng should have put the Magpies ahead 10 minutes earlier, but slotted his shot wide of the post after bursting clean through. Chris Eagles had United’s best effort of the first half, but his low shot was saved by Fraser Forster after six minutes.
United went into half-time a goal behind, and also hampered by the loss of Rodrigo Possebon through injury. The elegant Brazilian was substituted as a precautionary measure after an awkward landing just after Newcastle’s goal.
Solid all evening in defence, Silvestre was involved as United drew level on 54 minutes, curling a superb ball into the area for the onrushing Macheda to control and stab home with the outside of his right boot - his first Reserves goal.
A minute later, Welbeck controlled a fine chipped pass from skipper Tom Cleverley inside the area and, despite briefly losing possession he recovered the ball, executed a sublime drag-back to find space and lashed a left-footed shot into the top of the net.