Newsham dispatched United's third goal beyond defender Gavin Cowan, who had assumed the keeping duties following Dimitar Evtimov's red card.
The Boston United frontman admitted some nerves facing an unfancied stand-in, but backed himself to bag his sixth goal of the campaign.
Newsham discussed United's deserved win, overcoming some old friends and what success in the FA Trophy would mean ahead of the forthcoming Workington tie at The Jakemans Stadium.
Danny Sleath's video reaction will follow on bufc.co.uk.