First-half strikes from John McAtee and George Lloyd put Grimsby on course to a comfortable 3-0 win at Crewe.
Substitute Tom Dickson-Peters sealed victory for the Mariners with a close-range finish late on.
The visitors got off to a great start when Lloyd’s clever flick released McAtee and the attacker raced clear before curling the ball into the far corner from 20 yards in the third minute.
Crewe responded with Callum Ainley curling a free-kick the wrong side of the post.
Grimsby full-back Daniel Amos drove a long-range effort that flew just past the far post.
Lloyd doubled the lead in the 31st minute when he picked up a loose ball on the edge of the box and drove a low finish into the bottom corner.
The Mariners continued to pose a threat, with Harry Clifton being denied by the long reach of Dave Richards.
However, the home keeper was beaten by Dickson-Peters, who fired in the third off the far post in the 84th minute after Amos mishit his effort across the six-yard box.