Second-half goals from Scott Garner and Liam Hearn helped Grimsby come from behind to beat local rivals Lincoln.
gave the Imps a 33rd minute lead after a jinking run, before Garner headed the Mariners level from Michael Coulson's corner.
Cambridge loan man Conal Platt
Hearn's 18th goal of the season just past the hour, latching on to Craig Disley's pass, proved to be the winner.
Anthony Elding hit a post from another corner by Coulson but that miss did not prove costly as Grimsby held on.
VIEWS FROM THE DRESSING ROOM
Lincoln City manager David Holdsworth told BBC Lincolnshire:
"In the first half we were fantastic but really we paid the price of not putting the chances away.
"You want that second goal and I think if we'd got that we would have gone on to be worthy winners.
"But that's football, and a 10-minute spell in the second half has cost us."
Grimsby Town joint-manager Paul Hurst told BBC Radio Humberside:
"The first half certainly belonged to Lincoln and I thought we dominated most of the second half and looked dangerous.
"I kind of threw it back to the players at half-time, not to give me excuse of the way the formation Lincoln were playing.
"I just thought we were second best really but thankfully we got a reaction and we played something like we can in the second."
Lincoln City 28 Farman 02 Hinds 03 Nutter 05 Gowling Booked (Beardsley - 60' ) 13 Sinclair 08 Power 27 Christophe 34 Thompson (Russell - 76' ) 36 Sheridan 11 Laurent (Perry - 69' ) 12 Platt Substitutes 01 Anyon 10 Beardsley 15 Russell 17 Nicolau 09 Perry Grimsby Town 13 McKeown Booked 15 Pearson Booked 22 Townsend 26 I'Anson (Garner - 19' ) 08 Disley 19 Wood 23 Panther 25 McCartney (Artus - 46' Booked ) 07 Coulson 10 Hearn 39 Elding Substitutes 06 Garner 11 Artus 18 Makofo 21 Thanoj 12 Duffy
Ref: Ross Joyce