Jaze Kabia scored an added-time equaliser as the Mariners recovered from two goals down to earn a 3-3 draw with Harrogate Town.
After a goalless first half in North Yorkshire, the hosts took the lead through Reece Smith but their advantage was cancelled out by Charles Vernam.
Town were level for just two minutes before Ellis Taylor put Harrogate ahead again from the penalty spot and substitute Conor McAleny looked to have sent the home side on their way to all three points when he made it 3-1 with 14 minutes to go.
But the visitors, roared on by a sold-out away following of 1,050, showed great character to get themselves a result, with Harvey Rodgers reducing the deficit to one goal before Kabia secured a point to ensure the Mariners continued their unbeaten start to the new Sky Bet League Two season.
Grimsby head coach David Artell named the same team that began last week’s home victory over Crawley Town, with goalkeeper Christy Pym protected by a defence of Rodgers, Doug Tharme, Cameron McJannet and Jayden Sweeney. George McEachran and Even Khouri were behind Darragh Burns, Kieran Green and Vernam in midfield, as Kabia again led the attack.
The bench was also unchanged, with Seb Auton, Jamie Walker, Justin Amaluzor, Geza Turi, Tyrell Warren, Cameron Gardner and Henry Brown all named as substitutes.
Harrogate were also looking to make it two wins out of two at the start of the new campaign, following an impressive away victory at Bristol Rovers last week.
Manager Simon Weaver named former Mariners Lewis Cass and Bryn Morris in his starting XI, while Ben Fox was among the subs.
FIRST HALF
Smith won an early corner on the home left and Tharme had to head it behind for another one. This time, Green headed away as far as Jack Evans, who volleyed wide from the edge of the penalty area.
Defender Tom Bradbury saw the first yellow card of the game on seven minutes for bringing Kabia down as he looked to make progress down the Town right. Vernam sent the resulting free kick into the box but it had too much power and bounced wide of the far post.
Green and Burns linked up well to create an opening on the right but they were unable to turn it into a chance in front of goal, then Stephen Duke-McKenna turned into the box at the other end but was booked for simulation after going down.
Warren Burell followed him into the referee’s notebook for a foul on Burns with 15 minutes on the clock, then Tharme had to clear a low cross from Evans as Harrogate continued what had been a bright start to the contest.
Town’s first chance came on 21 minutes, as Khouri pulled the ball back from the left. It broke for Sweeney but his strike from inside the box was blocked.
Vernam fired over the bar moments later after being picked out by Burns, then Sweeney saw a 20-yard strike take a heavy deflection which looped it through to goalkeeper James Belshaw.
Rodgers headed a Taylor cross behind for a corner just after the half-hour but the ball from the flag was cleared, then Vernam sent a curling strike over the bar from 25 yards after good play by Khouri.
Rodgers became the first Town player to be booked after a foul on 38 minutes, then McJannet needed treatment following a challenge near the centre-circle but was passed fit to continue.
Green hit the post on 44 minutes after Burns capitalised on a mistake in the home defence from a Tharme long ball, before Burrell made a block from Vernam as the half moved into two added minutes.
Burrell headed a Burns corner away from danger, then Green fizzed a low ball across the six-yard line as Town continued to attack, although nobody could get a vital touch on it.
That meant it remained goalless at the break after a half in which both sides had created good openings but both goalkeepers had remained untested.
SECOND HALF
No changes were made before the restart and an early Sweeney free kick bounced wide, then Burns became the latest to see the yellow card after a push on Burrell.
The deadlock was broken two minutes before the hour and it was Harrogate who took the lead. A quickly-taken free kick was played down the home left and SMITH cut into the box before beating Pym with a low strike to the far corner of the net.
Green got back to stop Duke-McKenna as the hosts immediately went in search of a second goal, then McEachran fired wide from 20 yards at the other end.
Shawn McCoulsky sent a low shot just wide from a narrow angle after beating McJannet, as Harrogate continued to look dangerous.
Walker and Amaluzor replaced Khouri and Burns in Town’s first two changes on 65 minutes and they were back on level terms three minutes later. Green sent a low cross over from the right and VERNAM got on the end of it to beat Belshaw from six yards.
But they were level for just two minutes, as Harrogate reclaimed the advantage from their next attack. Pym brought McCoulsky down inside the box and after the referee pointed to the penalty spot, TAYLOR confidently beat the keeper to make it 2-1.
Smith made way for new signing McAleny in the home side’s first substitution and the former Salford City attacker made an instant impact. Vernam lost possession to Morris near the halfway line and after the hosts worked the ball forward, McCoulsky held it up on the edge of the box for McALENY to send a curling strike past Pym.
Gardner replaced Sweeney on 78 minutes as Town looked for a way back into the game, with Tom Cursons and Tom Hill coming on for McCoulsky and Duke-McKenna in the yellow of Harrogate at the same time.
A Town corner on 82 minutes was dealt with but another opportunity came seconds later with a free kick midway inside the home half. McEachran sent it in and Gardner’s header looked destined for the net, only for Belshaw to produce a fantastic save to tip the ball away from goal.
Town were not to be denied for much longer though, and they were back within one goal with six minutes to go, as RODGERS drilled a superb 25-yard strike into the bottom corner of the net.
A shot from McJannet took a deflection for a corner as the Mariners aimed to haul themselves level.
But the hosts could have won the game on 89 minutes when a break led to Taylor getting the ball with time and space to cut into the penalty area, only for him to fire wide of Pym’s far post.
A minimum of six added minutes gave Town further opportunity to complete their comeback and snatch a point, with Brown replacing Green in their latest change.
And two minutes in, they had that crucial third goal. Gardner won a header which sent KABIA through on goal and the striker calmly rolled the ball past the advancing Belshaw for 3-3.
Anthony O’Connor was booked for a foul on Kabia as Town pushed forward in search of an unlikely winner, although McEachran’s free kick beat everybody and went out for a goal kick.
Gardner saw the yellow card for a foul in the centre-circle but the resulting Harrogate free kick was well-defended, then a good challenge by Burrell stopped a Town break.
That meant it finished all-square, with the Mariners claiming a valuable point to stay unbeaten after the first two games of the season.
Town are next in action on Tuesday, when they face Shrewsbury Town at Blundell Park in the first round of the Carabao Cup.#
Town: Pym, Rodgers, Tharme, McJannet, Sweeney (Gardner, 78), McEachran, Khouri (Walker, 65), Burns (Amaluzor, 65), Green (Brown, 90+1), Vernam, Kabia
Subs not used: Auton, Turi, Warren