But it truth the Stags should have returned home with all three points after taking a deserved 51st minute lead and spurning a string of great chances to have put the game beyond the home side.
Instead they were stung by a 73rd minute equaliser by Peter Bore to give the home side a point they probably didn't deserve over the 90 minutes.
The Mariners looked well short of the calibre of last year's team that reached the play-offs while Stags again hinted that they could yet have a season to remember.

Stags made one change with Buxton replacing the injured Hjelde (hamstring) in the centre of defence - his first start of the season.
Grimsby had defender McIntosh making his debut after signing on a month's loan from Huddersfield.
Home keeper Barnes safely gathered a dangerous low Hamshaw cross at his near post in the fifth minute while Bore dragged a shot well wide at the other end seconds later.

Grimsby defended another dangerous Hamshaw cross by conceding a corner which they eventually managed to clear.
Barnes failed to deal with a Mullins cross and was lucky he was able to push it away at the second attempt after failing to hold it.
Buxton did well to police Rankine in the box and block his shot and soon after Boulding was wide of the far post with a left foot effort from 18 yards.
Grimsby survived another spell of pressure after struggling to clear the visitors' second corner and Stags could be well pleased with their first 15 minutes' work.

Barker was frustrated by a second very late offside flag if the evening when he looked to be in on goal.
Then Barnes had to grab a Brown shot from a tight angle after the ball had reached him from a long Jelleyman cross.
But having done little in attack, the home side almost snatched a 21st minute lead when Rankine held off John-Baptiste to set up Bolland for a rising drive that thankfully deflected over for the first of two home corners.
Two minutes later Stags wasted an even better chance as Barker guided his header well wide from only six yards from Boulding's left wing cross.
Bore headed well over from the Mariners' third corner.

But it was the visitors who continued ti impress and Hamshaw's right wing cross on 38 minutes was controlled by D'Laryea in the box before teeing up Jelleyman for a ferocious strike that Barnes did well to tip over.
There were cruel cheers from both sets of fans as a John-Baptiste clearance struck referee Mr Olivier in the head and knocked him over as the break approached.

Barker came much closer in first half stoppage time as, under pressure, he just managed to get a head onto a Boulding cross and the ball just dropped the wrong side of the post.
But Mansfield went in al square and pleased with their first half display.
After an early burst of home pressure Stags were soon on top again and causing problems at the other end.
And they finally took a deserved lead on 51 minutes. Boulding put the ball int the box from the left and the ball eventually found Hamshaw who made space for himself before drilling home a superb low finish.
Stags fans were still celebrating when Brown found the net again a minute later from a through ball but the offside flag was already raised.
The game was now alight and Brown's deflected shot saw the ball spin into the path of Barker right in front of goal where Barnes had to smother his close prod.

That chance sparked a frantic spell of Grimsby pressure at the other end where Muggleton was the hero on 58 as Beagrie's clever through ball put Newey in on goal with the keeper to beat only to see Muggleton make a brilliant block.
Buxton cleared a corner from right in front of goal after Muggleton was unable to get neat it and the home side also had a couple of hopeful pot shots from outside the box

Birchall replaced Boulding down the Mansfield left on 62 minutes. And two minutes later Jelleyman was booked for a late tackle on Bore.
Brown was warned by the referee for remonstrating with the linesman over an offside decision and soon after left the field to be replaced by Reet. At the same time McDermott was replaced by Croft for the Mariners.
But Grimsby levelled things up on 73 minutes. Newey launched a long cross to the back post where Bore headed powerfully at goal. The ball hit the underside of the bar and dropped down to be cleared. But it was ruled the ball had crossed the line and Bore celebrated in the arms of the club mascot before limping off with a knock to be replaced by Harkins.
Rankine was then too high with a header from Croft's forward ball and alarm bells were starting to ring for the visitors with 14 minutes still to play.
However Stags had another great chance on 78 as the home defence were caught square and pushing up to halfway by Mullins' quick forward return ball and Barker was suddenly in on goal. But just as he pulled his foot back to finish, Newey appeared from nowhere with a brilliant saving tackle in front of goal.

Barnes then had to get down smartly on 81 to parry a 20 yard blast from Dawson after he was afforded too much space just outside the box.
Another scramble in the home box ended with Hamshaw lofting a tame finish straight at Barnes.
Grimsby threw centre half Futcher on up front for striker Jones for the last two minutes.
Muggleton punched clear a Grimsby corner in the 90th minute as the board was raised to show three extra minutes to play.
But it was left to Stags to miss yet another great chance with the last kick of the game as Hamshaw lifted a great ball over the top to put Dawson into a one on one situation. He looked a certain scorer and the away bench were up celebrating before watching in horror as the ball dropped the wrong side of the post.