The Mariners’ pair struck on 51 and 71 minutes respectively as David Artell’s side secured the win.
United were not without chances, with visiting keeper Jake Eastwood in excellent first half form, while his replacement Jordan Wright denied Keaton Ward late on, before Jacob Hazel rattled the post.
United (first 60): Cameron Gregory, Cameron Green, Mitch Roberts, Tom Leak, Martin Woods, Dan Mooney, Tony Weston, Jordan Richards, Sam Osborne, Frankie Maguire, Zak Mills.
United (final 30): Jake Lovelace, Michael Bostwick, Keaton Ward, Jacob Hazel, Adam Marriott, Dylan Hill, Jacob Scott, Ed Daffern, Ellis Perry-Burdett, Trialist B, Trialist C.
Referee: Darren Drysdale.
Attendance: 832 (214 visitors).
PIC: Russell Dossett.