Guernsey captain Blair Campbell says the club will have to strengthen in the summer as they prepare for their first campaign in National Three rugby.
The island side won the London One South title at the weekend and earned promotion to National Three London South East, the highest level Guernsey have played at.
"We're going to have to lift our game," Campbell told BBC Guernsey.
"The difference between London One and National Three seems like a big step."
It is a second successive promotion for Guernsey Rugby Club, and Campbell says the players must now work hard on improving their skills if they are to ensure they can compete at the higher level.
"We've seen other sides go up there and struggle a little bit.
"We're under no illusions that we're going to have to up our training and up our skill levels.
"Maybe we'll get a couple of acquisitions during the off-season, but we're pretty confident that we can make an impact, we'll have to see how it goes."