The Magheralave Road school was unable to field a team against Belfast Royal Academy in the crunch tie which had been scheduled to be played this morning.
Commenting on social media today, a spokesperson for the school said: “Since FSL have been unable to safely field a full team, Friends’ accept that BRA will progress to the next round.
“Thank you to everyone for your support over the last few days. Best wishes to BRA in the semi-final!”
A spokesperson for Ulster Schools Rugby tweeted: “Friends’ SL accept the decision of Ulster Branch and confirm that they have forfeited the QF cup game against BRA today.”