CBC pupils have been banned from attending the school's opening Munster Schools Senior Cup tie against Castletroy College at Musgrave Park, Wednesday at 2.15pm.
The famous rugby school, which won a record 30th title, when defeating great rivals, PBC, 5-3 in last year's final, have been hit with a one-match suspension.
The Munster Branch of the Irish Rugby Football Union imposed the ban following a pitch invasion at the end of the game as Christians celebrated reaching a significant milestone in the long history of the competition.
It means the school will have no support at the game, which is the middle match in a triple-header, starting with Bandon Grammar School-Rockwell College at 12pm and finishing with PBC-Crescent College Comprehensive at 4.30pm.
Christians has over 1,000 students between the secondary and primary schools and their teams, both in the senior and junior cups, are always well supported.
“It's disappointing that we will have no fans at the game,” said a school spokesman.
“We always attempt to maintain the highest standards, but it's difficult to impose a thing like stopping excited youngsters from going onto a pitch at the end of a big final.
“Last season's final was against our biggest rivals and naturally fellows wanted to celebrate winning with their friends at the end.
“We were in a final in Limerick in recent years, when we had 13 bus-loads of supporters.”
Irate parents, who contacted the Echo, were incensed at the decision. “It's very short-sighted and doesn't reflect well on the organisation,” said one, who did not wish to be named.
The Munster branch were asked to comment.