Justin Obikwu’s goal gave the Mariners a fourth straight away win and a first victory over Tranmere Rovers at Prenton Park since December 1998.
After the disappointment of home defeat on Saturday, Town bounced back in style to continue their excellent run of form on the road and pick up another well-earned three points.
Clear chances in the first half had been limited to one for each side, with Obikwu’s header the closest the visitors came to breaking the deadlock before the break.
But Town created the better second-half opportunities and after Danny Rose saw a penalty saved by Tranmere keeper Luke McGee, his strike partner went on to grab the only goal of the game.
And after taking the lead, the visitors defended resolutely to ensure a hard-working display was rewarded with maximum points.
Four changes were made to the Grimsby starting XI for the trip to Merseyside, with Doug Tharme, Tyrell Warren, Callum Ainley and Obikwu replacing Lewis Cass, Jason Svanthorsson, George McEachran and Cameron Gardner from the team that began the weekend defeat by Walsall.
Jackson Smith continued in goal after his emergency loan from Barnsley was extended for another seven days, while Harvey Rodgers and Cameron McJannet joined Tharme in a back three. Warren and Denver Hume were deployed as wing-backs, with Ainley, Evan Khouri and Luca Barrington in the centre of midfield as Obikwu started alongside Rose in attack.
Cass, McEachran, Svanthorsson and Gardner were all named on the bench, along with Seb Auton, Matty Carson and Donovan Wilson.
Tranmere had drawn five of their 11 Sky Bet League Two games so far this season but were looking for back-to-back wins after a 2-1 away success at Bromley on Saturday.
Manager Nigel Adkins made three alterations to his team, with Connor Wood, Kieran Morris and Sam Taylor all coming into the XI.
Rose headed clear from a Cameron Norman long throw as the hosts were the first to attack, then Lee O’Connor was caught offside when running onto a through-ball as Tranmere came forward again on 10 minutes.
A dangerous-looking low cross from the home left was just out of striker Luke Norris’ reach, before Town’s first sight of goal led to a blocked shot from Obikwu.
The Mariners were growing into the game by the quarter-hour mark and Obikwu won the first corner but Hume’s left-wing delivery was headed wide at the far post by Rodgers.
Smith got down to stop a long-range effort from Morris, before McJannet headed clear from an Omari Patrick cross.
Tranmere were inches away from taking the lead when Morris met a pull-back from Patrick but Smith got a hand to his shot and McJannet reacted the quickest to clear the ball off the line. Town launched a counter-attack and home stopper McGee was shown the game’s first yellow card for a foul on Rose after rushing away from his penalty area.
A Town free kick was dealt with at the other end, before the away side’s best chance so far came on 34 minutes. Hume burst forward and linked up with Ainley, who played the ball wide for Warren to cross but Obikwu’s header went over the bar.
Hume blocked a Taylor shot from the edge of the penalty area on 37 minutes, then Taylor was involved again but his weak strike was comfortable for Smith.
Ainley fired wide and Rose was also off-target with a header as Town looked for a breakthrough before half-time but it was not to come and after one additional minute, the game remained goalless at the break.
SECOND HALF
No changes were made before the restart and Town looked to have an opening when Ainley made progress through the middle and looked for Obikwu but the striker could not get a shot away.
Norris headed off-target from a Wood cross at the other end, before Hume created a great opportunity with a low cross from the left, although Obikwu could only guide his volley over the bar.
Town were starting to get on top and eight minutes into the half, they were given the chance to take the lead. Khouri won the ball in midfield and broke forward before finding Rose, whose pull-back struck the arm of Norman. The referee pointed to the penalty spot but Rose could not take advantage as his kick was saved by keeper McGee.
O’Connor cleared the bar from 25 yards for Tranmere, before Norris headed wide from a Wood cross but was adjudged to have fouled Hume in the process.
Hume did well to stop Taylor and win the ball as the hosts looked to put pressure on the Town goal but when the opening goal finally arrived just before the hour, it was the Mariners who opened the scoring. OBIKWU did well to beat the onrushing McGee to a long ball from Barrington and after touching it past the keeper, the Coventry City loanee rolled it into the empty net from a narrow angle on the left.
Ainley did well to block a Taylor strike for a corner at the other end and after the flag-kick was cleared, the pressure continued and Norris and Tom Davies both went close in a goalmouth scramble but it was eventually well-defended.
Norris sent the ball across goal and wide of the far post as the hosts attacked again, then Gardner replaced Obikwu in Grimsby’s first change on 66 minutes.
Smith was booked for time-wasting three minutes later, before Tranmere’s O’Connor also had his name taken by the referee for a foul on Warren.
McJannet almost got on the end of a looping header across goal from Rose after Tharme had found the striker, then Josh Hawkes and Harvey Saunders replaced Patrick and Taylor in a double-substitution for the home side.
A Hume free kick from the left was headed clear ahead of Gardner as Town looked to add to their lead with 15 minutes remaining.
The hosts then had a free kick in a dangerous position when Barrington fouled Norris, although good defending by Rose saw him head the ball out for a corner after Sam Finley’s chip into the box had been met by Davies.
Ex-Town loanee Connor Jennings replaced Morris in the Tranmere attack, while McEachran was sent on in place of Barrington for the away side.
Defender Jordan Turnbull was booked for dissent after a free kick was given against him with 10 minutes to go, then Norris became the latest to see the yellow card as the hosts’ frustration grew, while Tranmere boss Adkins was also handed the same punishment.
Cass replaced Ainley for Town with 85 minutes on the clock, as the home side pushed forward in a bid to rescue a point.
Norris was denied by Smith just before the game moved into a minimum of seven added minutes, with Regan Hendry replacing O’Connor in Tranmere’s latest change.
The yellow card came out again as Davies was booked for dissent and as the pressure built, Town were given some respite when Hendry became the latest to be booked, for simulation as he aimed to win a penalty.
Norris slipped in a chase with McJannet as Tranmere continued to come forward and this time, it proved to be their last opportunity as Town dug in to see out the remainder of the contest and claim the points.
The Mariners are next in action on Saturday, when they host Milton Keynes Dons at Blundell Park.
Town: Smith, Rodgers, Tharme, McJannet, Warren, Ainley (Cass, 85), Khouri, Barrington (McEachran, 79), Hume, Rose, Obikwu (Gardner, 66)
Subs not used: Auton, Carson, Svanthorsson, Wilson
