An early goal was enough to give Cowdenbeath three vital points at Montrose and allowed them to continue their push for promotion.
The goal came after three minutes when Mark Baxter crossed from the right and Markus Paatelainen volleyed home from the near post.
Four minutes later Andy Jackson sent in a cross and Paatelainen had a volley saved by Andy Reid.
Montrose tried to hit back, and after 22 minutes a Kerr Dodds drive was saved by David Hay.
Back came Cowdenbeath and John Ward headed over. Then after 34 minutes Paatelainen headed wide from a Jackson cross.
Cowdenbeath should have stretched their lead after 39 minutes when Ryan McCallum headed over from close range.
Cowdenbeath were out of luck again after 47 minutes when Jackson crossed for Graham Guy to crash a header against the post.
After 57 minutes a Ward header from a corner was saved by Reid. Montrose came close to equalising in the next minute when a drive from Elliott Smith forced a fine save from David Hay.
After 74 minutes a Jackson shot seemed to be heading for the Montrose net, but when McCallum touched the ball home the flag went up for offside.
Montrose were reduced to 10 men three minutes from time when Neil Stephen was sent off for a second booking.