The now departed Martin Paterson and Illness to Danny Boshell enforced Town boss Alan Buckley to make two changes.
Danny North was handed the lone striker role, Gary Croft came into make up a fifth midfield player.
It turned out to be the proverbial game of two halves, with Macclesfield 2-0 up at the break, and the Mariners coming out and totally dominating the second half. If Town had produced the second half display in the first half they might have been coming away from Moss Rose with all three points.
Macclesfield started brightly with Town not getting a look in early on, and the home side were ahead after just 5 minutes.
From a Maccl corner, the referee stunned the Town players and travelling support by pointing to the penalty spot. Presumably for a push by Justin Whittle?
McIntyre stepped up to fire the spot kick high past Barnes.
On 15 minutes Toner saw a cracking volley go just over the bar.
But on 19 minutes it was 2-0. A long throw from the right was flicked on at the near post by Murphy to Heath, and despite the ball being behind the striker, his overhead kick flew past Barnes and into the net.
With 24 minutes played Alan Buckley decided to change things, with Gary Croft making way for Gary Jones as Town switched to a 4-4-2.
The two goals apart, neither keeper was forced into any serious action during the first half.
Two minutes overtime was added by the referee.
Half-Time: Macclesfield Town 2 Grimsby Town 0
John McDermott replaced Matthew Bloomer at the start of the second half.
Town started the second half well and began to dominate. The Mariners got their first shot on target on 55 minutes, as Fenton's shot was easily saved by Lee in the Macclesfield goal.
Disappointingly Bore and North seemed to get in each other's was way and a good chance was lost.
A mix up in the Town defence allowed Tipton in but Barnes pulled off a fantastic save to keep the Mariners in it.
GOAL. 72 minutes. Good play by Hunt who pulled the ball back for Hunt, the ball came off a defender and fell nicely into Jones' path to calmly side foot home.
Good play between Bore and North saw Bore misread the ball and his effort went tamely wide.
The fourth official signalled four minutes of added on time.
Macclesfield almost made it three in added time. Barnes saved the initial shot from Murphy but the ball came back and Macca had to be alert to keep the Silkmen out.
The home side held on and prevented the Mariners grabbing a point, a point that their second half display deserved.
