Finn Harps goalkeeper Tim Hiemer.
Athlone Town 1 Finn Harps 0
Finn Harps fell to their second defeat of the season as Athlone Town's Dean Ebbe struck the only goal of the game in the first half.
Ebbe netted in the 24th minute and it proved to be the only separator at Lissywollen.
Darren Murphy's Harps not only missed a chance to close the gap on Cork City, but the Leesiders' 0-0 draw at UCD moves them four points clear at the summit.
Harps had big shouts for a penalty five minutes from the end when Sean O'Donnell went to ground, but referee Jason Moore waved away the appeals.
Harps have a tricky couple of assignments ahead with treks to Cobh Ramblers and Cork City over the next two weeks.
Goalkeeper Tim Hiemer was back after missing the 1-1 draw against UCD with an injury while Ryan Rainey was restored and Murphy handed a first start to Chris Lotefa, who is on loan for the season from Bohemians.
Harps fell behind around the midway point of the opening half when, after Oakley steered the ball back into the danger zone with a clever flick, the unmarked Ebbe headed past the wrong-footed Hiemer from six yards.
German Fuentes Rodriguez, who last month made his El Salvador debut when featuring in a 3-0 loss to World Cup winners Argentina in Pennsylvania, was back in the Athlone starting line-up here.
Rodriguez' inclusion was one of three changes made by Athlone manager Dario Castelo.
Armando Oakley and Rúben Candal were also in with Castelo shaking things up after a chastening 3-0 defeat in Bray the week beforehand.
Athlone began well with Carl Mujaguzi volleying over the crossbar on eight minutes.
At the other end, Harps captain Tony McNamee – who had scored in each of his last three outings – was off target from a free kick.
Harps looked for a way back, but Conor Tourish headed over the top before Rainey saw a 25-yard effort held by Enda Minogue in the Athlone goal.
Athlone almost doubled their lead as the interval approached but, having been teed by Aaron Connolly, Dan McKenna stabbed wide from just inside the D.
Minogue thwarted Harps just after the changeover when saving well to keep out Noe Baba's header.
Hiemer kept Harps' hopes alive with a fine stop in the 72nd minute, saving from Ebbe after Oakley made the incision down the right-hand side.
That came after Minogue came off his line to halt the advances of Success Edogun, but Harps openings were scarce.
With Harps throwing on Patrick Ferry and Mark Mbuli for the closing stages in a bid to get back onto level terms, Hiemer was called into action. The German stopped blocked a header by the Athlone replacement Jamar Camption-Hinds, who was picked out by an Oisin Duffy cross.
Athlone Town: Enda Minogue, Oisin Duffy, German Fuentes Rodriguez, Jarlath Jones, Armando Oakley, Brian Torre (Jamar Campion-Hinds 61), Aaron Connolly, Dan McKenna, Carl Mujaguzi (Divine Izekor 90+1), Dean Ebbe (Shane Forbes 90+1), Rúben Candal (Gideon Tetteh).
Finn Harps: Tim Hiemer; Matthew Makinson, Noe Baba, Conor Tourish; Jamie Watson (Aaron McLaughlin 89), David Cawley, Ryan Rainey (Patrick Ferry 76), Tony McNamee (Darragh Coyle 89), Shane McMonagle (Sean O'Donnell 60); Chris Lotefa (Mark Mbuli 76), Success Edogun.
Referee: Jason Moore.
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