Fra McCaffrey scored twice as Glentoran emerged 4-2 winners over Ballinamallard United at a wet and windy Ferney Park.
McCaffrey side-footed in from close range but Adam Lecky slotted the ball underneath Elliott Morris to equalise.
Jonathan Smith supplied the final touch to make it 2-1 to the Glens, Jason McCartney levelled with a penalty, then McCaffrey netted with a deflected shot.
Curtis Allen made the points safe by sliding in to connect with Smith's pinpoint cross from the right.
McCaffrey opened the scoring in the 23rd minute with a relatively simple tap-in after Stefan McCusker had saved with his feet from Allen.
Lecky restored parity 10 minutes later after McCartney's cross had been knocked into his path by Steve Feeney.
Nine minutes into the second half, Smith nudged the visitors ahead after Steven McCullough's driven ball across the area came off a couple of defenders and was then diverted into the net.
McCartney's 64th-minute spot-kick brought the teams level again, but strikes from McCaffrey (72) and Allen (83) ensured Alan Kernaghan's outfit left Fermanagh with all three points.