The crucial moment in a game, which will not live long in the memory, came in the 16th minute when Grimsby goalkeeper Steve Mildenhall saved a Colin McMenimen penalty. But this in truth was a game of precious few chances and a match neither side could justifiably claim they deserved to win.
The home side were awarded their spot-kick when striker Kelvin Langmead was bundled over by Mariners centre-back Rob Jones. Referee Melin had no hesitation in pointing to the spot - but McMenimen, who has already successfully netted from the penalty-spot three times this term, saw his poorly struck kick easily saved by Mildenhall diving to his right.
Langmead, recalled to the side after serving a three-match ban for his sending off against Notts County a fortnight ago, was brought back to replace Jamie Tolley, who was sent off in the midweek draw against Barnet. This was the only change from Tuesday in a Shrewsbury team who, despite having a greater share of possession, were unable to seriously trouble a well-marshalled Grimsby rearguard.
At the other end it took the visitors until the dying seconds of the first-half to trouble Shrewsbury's teenage goalkeeper Joe Hart - who, for the third time this season, was watched by Premiership outfit Manchester City.
Watching City scout Tim Flowers would once again have been impressed when Hart saved excellently from Michael Reddy on the stroke of half-time and then again from the hard-working Reddy five minutes after the restart.
From that point onward there was nothing to separate the teams in terms of effort and endeavour, but a goal rarely looked likely, with a long shot from Shrews' midfielder Neil Sorvel on 70 minutes the only effort of note in a far from gripping second half.