Guernsey FC beat Premier Division side Ash United 4-1 to make it through to the next round of the Combined Counties League Premier Cup.
Ryan Zico Black gave Guernsey the lead with a third-minute free-kick before Chris Tardif saved a penalty.
Ross Allen made it 2-0 after 49 minutes before Kieron Mahon got a third.
Guernsey conceded a first-ever home goal when Paul O'Donnell headed in on the hour before Craig Young marked his return from injury with a late fourth.
The win sets up a meeting for the runaway Combined Counties League Division One leaders with Premier League table toppers Egham Town at Footes Lane on 24 January.
"That's what we're here for, we want to improve ourselves as players and improve ourselves as a team and these are the games you want to be in," Tardif told BBC Guernsey.
"The league's the number one priority, as simple as that. I'm sure the chairman will be pleased that we're through," added manager Tony Vance.