Gradi Lomboto scored his side's winning goal.
Athlone Town moved up to fourth in the First Division thanks to their win over Finns Harps on Friday.
Gradi Lomboto scored a late winner to seal a 2-1 win over the Donegal opposition and give town back to back league wins.
Gavin McAteer's 69th minute strike had cancelled out Callum Cleary's opener.
Town now turn their attention to games at home to Kerry this Friday before travelling to Longford town next Monday.
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