VAUXHALL travelled to Nottingham with optimism on Saturday, but the home side raced into a 2-0 lead inside 13 minutes, with two deflected goals, credited to Dolby and Bettney.
The Motormen twice went close when debutant Robertson put top scorer Fearns away, but Butler in the home goal denied both efforts.
On 31 minutes, it got even worse for the visitors, when Robinson headed Alfreton's third.
On the resumption, Vauxhalls continued to probe but on 57 min-utes, a quickly-taken free-kick caught the Motormen flat-footed and Godber fired a fourth. Ten minutes later, Robinson went clear, with the visitors expecting an off-side flag, to run in number five.
Motors lost keeper Higgins five minutes from time having clattered into a post, with Whelan taking over the gloves.
Cumiskey struck a fine late goal.
VAUXHALL: Higgins (Griffiths 85), Ward (McCann 67), McDermott, Robinson, Whelan, Lynch, Nesbitt, Lawton, Fearns, Robertson (McAuley 62), Cumiskey.