Guernsey head coach Jordan Reynolds believes his side should have beaten Chichester by more than the 22-15 scoreline in National Three London.
They remained at the foot of the table despite the win, but only one point adrift from second-from-bottom Tring.
Malcolm Barnes and Glen Walters scored early and Matt Hema's try soon after half-time put Guernsey 22-3 up before late a Chichester fightback.
"We probably should have won that game by 30 or 40 points," Reynolds said.
|Bottom of National Three London & South East|
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The victory was Guernsey's second in three games after beating Tonbridge Juddians on 13 December.
But they have won just four of their 15 games this season as injuries have hit Reynolds' squad hard.
He had 19 players unavailable for the Chichester game and was understandably pleased with the result, despite his side failing to convert a number of openings that came their way.
"We probably didn't put away three or four scoring opportunities," Reynolds told BBC Radio Guernsey.
"But I guess that's a little bit of confidence that we're lacking at the moment.
"Overall I think we defended well and I think we played quite well for 60 minutes on the game.
"We played the majority of the rugby for 60 minutes, so we were tiring in that last 20, and I think Chichester left it a little bit too late to take us on."