Ruben Rodrigues scored a last-minute winner to hand us a huge win at league leading Grimsby.
As the clock struck 90 in a game of very few clear-cut chances for either side, Rodrigues sent the away end into raptrues with a close-range finish after Matt Palmer's cross was parried into the danger zone.
Grimsby, who had won all six of their home matches ahead of our arrival, had looked the more likely side to score in a closely-contested affair at a cold and blustery Blundell Park.
Lenell John-Lewis looped a shot on to the bar and Erico Sousa sliced an effort wide in the first half, with Ian Burchnall replacing Jim O'Brien and Dion Kelly-Evans with Cal Roberts and Aaron Nemane in a half-time shift to a more attacking approach.
A more even second half was to follow, with Roberts stinging the keeper's palms with a shot from the edge of the area before Rodrigues stepped up to the plate on the brink of stoppage time.
STARTING XI: Patterson; Cameron, Rawlinson, Brindley; Taylor, Kelly-Evans (Nemane 46'); Palmer, Vincent (Francis 78'), O'Brien (Roberts 46'); Rodrigues, Wootton
SUBS: Chicksen, Mitchell