A Melbourne Heart defensive blunder gifted Adelaide United import Jeronimo Neumann the match winner in a 1-0 triumph in Saturday's A-League encounter at Hindmarsh Stadium.
Neumann's second-half strike ensured Adelaide will end the round no lower than second on the table, the Argentine benefiting from a mistake by Heart stalwart Simon Colosimo.
The Melbourne defender, under little pressure in the 58th minute, butchered what should have been a routine clearance by inexplicably passing straight to Adelaide's Marcelo Carrusca.
Carrusca delivered to Neumann, who closed on goal and launched a shot from 10 metres.
Colosimo, diving to try and block the shot and make amends, had his agony compounded when Neumann's left-footer deflected from the defender's leg and into the net.
Adelaide's fifth victory from seven matches came after the Heart opened strongly on foreign turf.
But the visitor's captain Matt Thompson missed two genuine chances in the initial 20 minutes and the tide rapidly turned in the latter stages of the half.
The Reds crafted a series of scoring opportunities with Fabio Ferreira, Neumann and Evan Kostopoulos all unable to score from threatening positions.
Adelaide logged five shots on target to one in the opening half but Heart goalkeeper Clint Bolton was on song, denying both Neumann and Ferreira with spectacular saves.
Bolton instinctively thrust an arm into the path of the ball as Neumann charged at him in the 38th minute and nine minutes later produced a fine diving save to his right to steer from danger a Ferreira left footer.
But Bolton could do nothing to prevent Neumann scoring for the fourth time this season as the Heart slipped to their fourth loss of the season - and fourth defeat in their past five games.
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