Two late goals condemned Sevenoaks Town to a second successive Bostik League South East home defeat.
Hosting their final fixture before Christmas, they hit the woodwork twice and created several chances, especially in the second half, but boss Micky Collins admitted Oaks paid the price for “switching off” twice costing them any reward in this first-ever meeting between the two clubs.
Alfie Fleming, a 17-year-old second year scholar with Leyton Orient made his debut at left back, while another new signing Josh Dorling was on the bench following his move from league rivals Sittingbourne.
Fleming replaced Greg Benbow who left the club last week to concentrate on his new career as a London taxi driver.
William Johnson-Cole headed against the bar in the first half, while Kenny Pogue was foiled at the end in the second half as Oaks pressure failed to break the deadlock.
Pogue’s low first half effort was parried by visiting keeper Callum Stanton, before home opposite number Ben Bridle-Card made two important saves in the space of a minute.
He tipped Will Fazakerly’s effort over the bar, and denied Kieran Mahon with a block with his chest inside the six yard box.
Fazakerly fired inches wide immediately after half-time, but Oaks pressed themselves, but lacked a cutting edge, with Johnson-Cole (twice), substitute Ainsley Everett and skipper Frankie Sawyer all going close.
Guernsey, with only one away win all season pounced twice late on to claim the points.
Matt Loaring’s close range finish broke the deadlock 10 minutes from time, before substitute Seb Skillen completed the victory in stoppage-time.
Collins had confirmed that Xavier Vidal will miss the rest of the season after being injured at Whyteleafe.
He underwent an operation last week to re-set his patella tendon.
Oaks travel to Ramsgate on Saturday.