Caolan McAleer's first goal of the season was enough to give Airdrie United a 1-0 win over Dunfermline Athletic.
Dunfermline were looking for a third successive victory to strengthen their grip on second place and they started well, with Ryan Williamson stinging the palms of Grant Adam.
But it was Airdrie who hit the front with their first real attack after 18 minutes when McAleer found space to hammer into the top corner. They could have gone further ahead eight minutes later but Ryan Scully parried a Jamie Bain shot.
Allan Smith hit the post for Dunfermline after 32 minutes, while their best chance to pull level came after 72 minutes with Jordan Moore firing wide from six yards.