Battling Shrewsbury put a dent in Grimsby’s play-off hopes after they came from behind in a 1-1 draw.
Jaze Kabia saw a goal chalked off for the visitors after he was adjudged to have strayed offside.
Anthony Scully struck wide of the mark on the half-hour as the hosts threatened.
The Mariners had a penalty in the 37th minute when Jamie Walker was felled in the box, with Charles Vernam thundering home his seventh goal of the campaign.
Experienced striker John Marquis, the Shrewsbury skipper, levelled deep in first-half stoppage time as he met Sam Clucas’ cross with a bullet header.
Shrews keeper Will Brook denied Darragh Brooks after the break, before producing the save of the night to keep out Kaze from point-blank range.
Evan Khouri squandered a good chance to win it with 15 minutes to go when he turned Harvey Rodgers’ cross wide.
Shrewsbury are two points above the drop zone, while Grimsby are three points off the play-off pace.
