The Rooks made the brighter start as both Hollie Olding and Anna Grey tested Lionesses keeper Grace Moloney early on.
But the visitors hit the front after a defensive mix-up allowed Paige Satchell to steal in and smash home the opening goal on 16 minutes.
The capital side went in search of a second but found Sophie Whitehouse in inspired form, denying Danielle Carter with a smart save from her close-range effort.
Lewes improved after the interval with Reanna Blades seeing a strong penalty shout waved away after a mazy run down the left wing.
They pulled level just before the hour mark when Hollie Olding poked home after pinball in the 18-yard box.
The Rooks were pouring forward in search of a winner as Olding’s 30-yarder fired narrowly over and Sarah Brasero-Carreira skimmed the bar with a powerful strike.
Lewes got their just desserts on 79 minutes when Anna Grey curled home a sumptuous free-kick to secure much-needed maximum points for the south coast side.
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