Mark Hulme’s first-half goal sealed victory for Fleetwood against Grimsby.
Hulme scored the only goal on his debut as the Cod returned to League Two with a win.
Grimsby were actually the better starters of the two but failed to make the most of early opportunities, with Charles Wernam’s shot deflected and Jason Dadi-Svanthosen’s effort blocked On the goal line.
Fleetwood gradually found their feet and went close when Ronan Coughlan was picked out by Tommy Lonergan, with Mariners goalkeeper Jordan Wright in good position to make the save.
But Fleetwood scored first in the 18th minute. Mackenzie Hunter whipped a low pass through a crowded area and Hulme neatly slotted the ball into the bottom corner.
The break killed both sides’ momentum as play was halted midway through the half due to a medical emergency in the crowd. Coughlan did put the ball into the Grimsby net shortly before half-time, but the offside flag had been raised.
Danny Mayor and Hunter both had chances to double Fleetwood’s lead in the second half, but Mayor could only fire at Wright and Hunter’s shot was blocked.
However, Grimsby failed to cause any real problems for Fleetwood’s defense and Hulme’s goal was enough to get the home side the points.