The hosts hit the men from Nyewood Lane with four goals in the final 17 minutes of the first half, with Denzelle Olopade, Olly Box, George Whitefield and Josh Hill all on target.
The Rocks’ disappointment was compounded when skipper Calvin Davies was sent off 12 minutes from time after picking up two yellow cards in a matter of minutes.
It leaves the team rooted to the bottom of the Isthmian premier division – with a big week ahead of them. They’re at Eastbourne Borough in the Sussex Senior Cup on Tuesday then host Whitehawk – who are one place and one point above them – next Saturday.
See Dartford-Rocks pictures by Lyn Phillips and Trevor Staff on this page and those linked, or if you’re on the Observer app, just by scrolling down the single page.