A technique involves collecting formation fluids through a single packer having at least one drain located within the single packer. The single packer is designed with an outer layer that expands to create a seal with a surrounding wellbore wall. The drain is located in the outer layer between its axial ends for collecting formation fluid which is routed from the drain to an axial end of the outer layer via a fluid flow passage. Mechanical fittings are mounted at the axial ends of the outer layer, and at least one of the mechanical fittings comprises one or more flow members coupled to the flow passage to direct the collected fluid from the packer. The one or more flow members are designed to move in a manner that freely allows radial expansion and contraction of the outer layer.