A goal just three minutes from the end of normal time by Roscommon livewire Senan O'Grady left Fermangh nursing their second NFL Division Four defeat of the season.
O'Grady's last gasp effort sealed a gritty 1-12 to 1-9 win for the westerners in Kiltoom and leaves the Ernesiders rooted on just three points from four games.
Fermanagh were a goal to the good as early as the fourth minute and a point apiece from Paul Ward and Tommy McElroy help them take a 1-4 to 0-5 lead into the interval.
Points from Ward and Ryan Jones kept Fermangh in the driving seat, but Roscommon hit four points without reply to level, 0-11 to 1-8, after 63 minutes with free-taker Jack Rogers unerring in particular.
Roscommon upped the pace and O'Grady's clinical finish leaves them well positioned for a promotion berth.
Meanwhile in the top flight, 14-man Dublin hit seven unanswered points between the 40th and 56th minutes to run out 0-13 to 1-9 winners over Monaghan in Clones.
Dublin were 0-5 to 0-0 in front after 14 minutes before an opportunist fisted goal by Conor McManus in the 22nd minute helped the hosts claim a 1-5 to 0-6 half-time lead.
Dublin steamed into a 0-13 to 1-6 lead after 57 minutes and the dismissal of Diarmuid Connolly on the hour mark gave Monaghan a lift, but despite points from Christopher McGuinness, Tommy Freeman and Paul Finlay (free), they just fell short of getting something from the match.
Elsewhere, Cavan are now perilously close to the relegation zone after losing their Division Three clash in Limerick 0-15 to 2-14.
Limerick led throughout and weren't at all flattered by their 0-10 to 0-5 interval lead.
A goal in the 46th minute by Stephen Kelly gave Limerick a six point cushion (1-10 to 0-7) but Cavan fought back to make it 1-11 to 0-14 after a 65th minute goal by centre-back John McCutcheon.
Limerick had a sting in their tail though. After Cavan had Stephen Jordan sent-off three minutes from time Pa Reneghan netted to leave the Breffni men with just three points from four games.