Lewis McCann's second-half strike secured a precious three points for Dunfermline Athletic as Airdrieonians suffered their sixth straight Scottish Championship defeat.
That outcome leaves Rhys McCabe's side seven points adrift of Dunfermline at the bottom of the table.
The winner came from a direct ball over the defence and McCann got there to scoop the ball over Kieran Wright in goal for the vital breakthrough.
It had been fairly even until then, but Airdrie had chances to go ahead when Luke Badley-Morgan was superbly denied by Tobi Oluwayemi and Lewis McGregor struck just off target.
Dunfermline ought to have gone ahead, though, early in the second half after great work from McCann down the left, but he squared perfectly for Kane Ritchie-Hosler who was denied by Wright.
The visitors had a strong claim for a penalty shortly after conceding when Cameron Cooper went down under a challenge by Oluwayemi, but referee Colin Steven was unmoved as Airdrie found themselves on the end of what could prove to be a damaging defeat.
What the managers said
Dunfermline Athletic manager James McPake: "We know it’s an important game. They are the only team below us. It was a tough game but it’s three points and we move on to next week.
"What impressed me the most was the character to see it out. I've been critical at times saying we should have been out of sight because of the chances we've been creating.
"We weren’t as creative as we have been but still created enough, but the important thing was we put one in the net, stayed strong and didn’t really look under any real of pressure."
Airdrieonians manager Rhys McCabe: "We created chances, we had an appeal that was a stonewall penalty and a clear foul on Rhys Armstrong that leads to their goal.
"They were huge moments in the game that didn't go our way. Coming away with a point would have been fair, if not all three.
"Seven points is a few games. It's not a position we want to be in but it's certainly something we can claw back."