Boston United's final pre-season match was soured by an injury to defender Scott Duxbury.
The left back left the pitch on a stretcher with his leg heavily strapped after being caught by Grimsby Town's John McAtee late in the second half.
The injury silenced what had been a lively crowd, before warm applause followed the defender down the tunnel.
While McAtee - the man who scored the only goal of the game - was then met with boos from the home crowd every time he touched the ball until his late substitution, the challenge had appeared innocuous enough at first glance.
Earlier this summer Boston boss Craig Elliott suggested Notts County could pose the Pilgrims' sternest test of pre-season.
But come full time this afternoon, it was another National League outfit who could arguably be handed that title.
Without the midfield trio of Paul Green, Shane Byrne and Andi Thanoj the Pilgrims weren't at their strongest in the centre of the park, while in attack Jordan Preston and Danny Elliott found themselves trying to feed off the same scraps too often.
But forget those minor issues, the Mariners had street smarts - quicker on the ball and stronger off it. Flashes of brilliance in attack and a few clever tugs of the shirt when dealing with balls over the top reminded United the levels they need to be striving for if they want their title ambitions to become reality.
But the hosts by no means allowed themselves to be bullied, Duxbury and Danny Elliott finding their names in the book and Luke Shiels lucky not to join them after hacking down Erico Sousa.
A crowd of more than 1,600 - aided by 700 from the north of the county - added a little edge to the encounter, a perfect warm-up for Boston ahead of next week's curtain raiser against Spennymoor Town.
Peter Crook made a good early save to get the crowd going, using an outstreched leg to deny Seb Revan.
The Mariners attacker was slipped through by a delightful defence splitting pass from McAtee after he'd skilfully averted a sliding Tom Platt challenge.
It was McAtee who went close with the next sight of goal, lashing wildly wide after the ball landed kindly in the Pilgrims' box.
McAtee made no mistake when handed a second opportunity, handing Grimsby a 37th-minute lead as he slipped into an empty net after being teed up by the unselfish Revan.
Seconds later and Boston's first shot on target arrived, Max Crocombe getting down to smother Danny Elliott's snapshot.
A combination of the post and substitute keeper George Sykes-Kenworthy denied Mariners replacement Sousa an early goal in the second half.
Boston found themselves more and more in the game as the second half wore on and Jordan Burrow went close with a diving header, but couldn't find the target.
Momernts after Duxbury's afternoon was ended, Sousa clipped the Boston bar and the same player was thwarted by Sykes-Kenworthy as he was sent clear.
The Pilgrims stopper also got a hand to McAtee's strike from distance, pushing the ball round the post.
At the death Scott Garner could have l;evelled things, but his header was wide of the mark.
PILGRIMS: Crook (Sykes-Kenworthy HT), Tootle, Duxbury (Ferguson 81), Platt, Shiels, Burrow, Elliott (Wright jnr 83), Wright snr (Garner 62), Dimaio, J. Preston (Rollins 62 (Hawkridge 74)), Leesley (F. Preston 83).
GRIMSBY: Crocombe (McKeown HT), Efete (Sears 69), Crookes (Waterfall HT), Fox (Spoked 69), Pearson, Coke, McAtee (Goundry 87), Clifton, Longe-King, Revan, Adlard (Sousa).
REF: Garreth Rhodes.
Att: 1,630 (702).
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