Connor Cullen’s goal just after the midway point of the second half settled the Isthmian South Central clash, with Rocks skipper Tommy Block sent off minutes later.
It means Danny Hollands’ side are now winless in three, although they remain second in the table, just a point off top spot.
They will look for better on Saturday, when they go to Windsor and Eton.
See pictures from Rocks 0 Egham Town 1 by Lyn Phillips and Trevor Staff on this page and those linked, and get the latest from the Lane in the Bognor Observer, out Thursday.
17. Lyn Phillips
Rocks v Egham Town, Isthmian SC division Photo: Lyn Phillips : Lyn Phillips and Trevor Staff
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