Peterhead stretched their unbeaten run to 10 games, making heavy weather of the win over a plucky Montrose team.
Manager Henry Hall felt his visiting side were worth all three points, but poor defending cost them dear.
Peterhead went two goals up with David Hagen involved in both. After 23 minutes he controlled the ball on the left side of the penalty area, before crossing to Craig Campbell who scored from 12 yards, despite keeper Michael Hankinson getting a hand to the ball.
In the 38th minute, Hagen sent in a cross at the second attempt to find the unmarked Craig Tully, and he headed the ball into the right side of goal.
Montrose pulled a goal back three minutes before half time, David Greenhill shooting through a ruck of players with the ball being deflected into the back of the net.
The visitors had the best of the second half, but again found themselves two goals behind after 73 minutes.
Keith Gibson sent substitute Robert Linn clear through the inside-left channel and the former Dundee striker shot low into the far corner.
Montrose fought back again and Graeme Sharp fired a waist-high shot into the net from 20 yards to ensure the result was in doubt right to the end