But there was no three points for Forfar Athletic who slipped to a 4-1 loss at Queen’s Park.
Both Angus clubs were afforded a free week when the cup started on Saturday, instead kicking off their campaigns on game day two.
There was a long journey north for Stewart Petrie’s Mo, but it proved to be a worthwhile one.
They started the game on the front foot and took the lead on 10 minutes through Blair Lyons.
Lyons was clearly in the mood and he doubled his side’s advantage just five minutes later to give the Links Park side a cushion.
On the half-hour mark Lyons made sure the match ball would be returning home with him when he netter his hat-trick.
Montrose looked to be on easy street but their hosts were determined to make a fist of it and pulled one back through Sean Butcher on 66 minutes.
Graham Webster settled matters in the first minute of injury time before the scoring was completed by Fraserburgh’s Zane Laird a couple of minutes later.
On Saturday Mo host Kilmarnock.
Queen’s Park hit three times after the break to see off Forfar.
Lee Kilday handed the Spiders the lead only for Stefan McLuskey to level the scores.
Both sides had chances before Queen’s Park stretched ahead through Scott Williamson, Lewis Moore and Kilday again. Hamilton visit Station Park this weekend.