A controversial penalty was enough to give Sligo Rovers their first win of the season at Eamonn Deacy Park.
Both sides went into this one on the back of three league defeats, but Sligo got an early boost when they hit the front after five minutes with a penalty.
Dinny Corcoran stepped forward and slotted home his second goal of the campaign to give the Bit O'Red a strong foundation in their quest for a first win of the season.
They continued to dictate the pace of the game and it took a superb goal-line clearance from Stephen Walsh to deny Corcoran a second goal two minutes later.
Galway struggled to hold on to the ball for periods, but they finished the opening half well with Enda Curran and skipper Paul Sinnott threatening.
President Michael D Higgins and the crowd of 1,762 did not have much goalmouth action to entertain them after the restart but Galway should have equalised but Brush saved Padraig Cunningham's header 13 minutes from the end of a disappointing Connacht derby.
Galway United - Hanley; Byrne, Garcia, Walsh, Horgan; Shanahan, Sinnott, O'Leary, Connolly; Curran, Keegan (Cunningham 70).
Sligo Rovers - Brush; Boylan, McManus, Folan, Dykes; Beattie (Puri 50), Cawley, Russell, Devaney; Corcoran (Nielsen 65), Cretaro (Wearen 83).
REF - N Doyle (Dublin)