Josh Rees gave Steve King’s visitors an early lead and Kai Corbett doubled the lead in the second half – and despite plenty of the play, Bridges could not find a response.
The result left Borough in sixth spot – only six points behind leaders Enfield Town – while Bridges are two off the bottom in 20th.
FA Trophy action comes next for both sides this weekend, with the Sports going to Leatherhead and Bridges at Dartford for first round ties.
See Lydia and Nick Redman’s pictures from Three Bridges 0 Eastbourne Borough 2 on this page and those linked. Get the latest local football in the Eastbourne Herald and Crawley Observer every week.
9. Lydia Redman
Three Bridges v Eastbourne Borough, Isthmian Premier Photo: Lydia Redman : Lydia and Nick Redman
10. Lydia Redman
Three Bridges v Eastbourne Borough, Isthmian Premier Photo: Lydia Redman : Lydia and Nick Redman
11. Lydia Redman
Three Bridges v Eastbourne Borough, Isthmian Premier Photo: Lydia Redman : Lydia and Nick Redman
12. Three Bridges v Eastbourne Borough pictures by Lydia and Nick Redman (8).jpg
Three Bridges v Eastbourne Borough, Isthmian Premier Photo: Lydia Redman : Lydia and Nick Redman