Marconi became the only side to defeat Manly United at Cromer Park in the 2022 National Premier Leagues NSW Men's season with a vital 1-0 win on Friday night.
With three games washed out at the weekend (including Sydney United 58's game with Sydney Olympic) the result temporarily moves the Stallions into top spot with only four rounds remaining.
Defender Nathan Millgate's second-half header was enough to secure all three points for the visitors in a game with limited opportunities due to the torrential rain.
Such is the closeness of the competition, seven teams are within four points of each other with two teams having a game in hand.
The Stallions next assignment is the local derby against Sydney United 58 on Sunday.
The Reds have a busy week with the Waratah Cup semi-final on Wednesday night (July 6) against the Bonnyrigg White Eagles at Valentine Sports Park at 7pm.
The Reds sit in eighth place on 22-points - 11-points behind the Stallions.
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