A late Dillon Nagle strike made up for two missed penalties.
Manager Danny Wood said: "It was nice to finally get our first win of 2020.
"Before kick off we pulled out Kieran Deacon from the starting 11 because of the knock he took in the friendly with Lancing Tuesday night.
"I thought we played with a good intensity and it didn’t drop for the entire 90 plus 12 minutes added on time.
"We created a lot of chances in the first half and was finding myself asking what we have to do to score.
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The Mavericks started the second half fast and won the first of two penalties but Nagle's effort was saved.
With changes being made the second penalty was this time saved from James Thurgar but Nagle followed it in with not much time left on the clock.
Wood added: "It’s been a frustrating three months - this the first back to back game we have had in a while and hopefully we can kick on for the last seven games.
"Next week we take on Billingshurst who have started to pick up results especially a 3-1 win against Hailsham and expecting another tough game."