However, Guernsey, who beat Jersey 35-27 in their annual Siam Cup grudge match at Footes Lane in May, took control as the second half wore on.
With Jersey having Jack Higgins in the sin-bin, Matt Armstrong scored the Sarnians’ sixth try with 10 minutes to go as they claimed a bonus-point victory.
The game was the first league meeting between the two island sides since the 1994-95 season when Jersey won what was then the Hampshire One title.
Jersey were initially set up as a separate amateur team for local players to play in the English leagues because of the success of professional side Jersey Reds.
But when the then Championship champions went bust in 2023 Jersey RFC became the main focus of rugby in the island.
They have gone on to win three promotions in four years to join Guernsey in the fourth tier of English club rugby.
“It was a tough contest,” Guernsey director of rugby Jordan Reynolds told BBC Radio Jersey.
“We probably had territory and possession for the lion’s share today and probably had a few things misfiring for us and few mistakes that we crept into our game.
“But I thought we were in control for the 80 minutes, which is great.
“Jersey’s a difficult place to come and get a win, you’ve got to fight the crowd as much as you’ve got to fight the opposition.
“So we’re just pleased to have the win, it’s five points on the road and we’ll bank that and we’ll move on to next week.”
Meanwhile Jersey director of rugby Myles Landick said he was disappointed with his side’s discipline, having seen two players get yellow cards:
“It’s frustrating, but they’re a really good side, credit to Guernsey,” he told BBC Radio Jersey.
“They put pressure on when it matters most, but you can’t help the frustrating parts of it.
“You can’t make that many errors and play 20 minutes of the game with 14 men, not against a side like Guernsey.
“They’re worthy for the win, but you can’t help but get frustrated at parts of that.”
