Guernsey hammered Knaphill in their first ever Combined Counties League match at Footes Lane on Saturday.
Glyn Dyer was on the end of a Dave Rihoy cross to open the scoring after 16 minutes.
Ross Allen struck the first of a hat-trick on the half-hour mark with Dom Heaume slotting home the fifth on the stroke of half-time.
Knaphill were restricted to long-range efforts, which did not prove a problem for Guernsey keeper Chris Tardif.
Nearly 1,500 fans turned out for the first UK league match ever played in the Channel Islands.
Guernsey assistant coach Colin Fallaize said: "We're really pleased and proud to get such a good result, I think we caught them cold in the first half."
Allen, who scored in all the side's pre-season friendlies, said: "It was a brilliant team effort, a great start, these are the important games now the season has started."
Guernsey travel to Hampshire for their first away game against Hartley Wintney on Tuesday.