Earlier this week, Kavanagh made the decision to default its scheduled round three game against John McGlashan College this Saturday when it became apparent it would not be able to get a team together due to a devastating run of early-season injuries.
Neilson said her 21-strong squad was down to just 11 available players and only nine of them were fit enough to train on Tuesday night.
The school has suffered two heavy defeats to start the season but it is the injury count which threatens to derail the campaign.
''We just have too many injuries, to tell you the truth,'' Neilson said.
''We thought if we defaulted this week and get everyone rehabbed so that we would be able to actually field a team on the 20th of May - that's our goal.
''There is only so much we can do. We have people in casts, basically, and that is the biggest problem because they won't come off in a fortnight.''
The list of injuries includes two concussions, a fractured ankle and a fractured wrist.
The side will reassess on Monday whether it can field a team for its round four match against Taieri College.
''The good thing about the boys is they are still coming along to support those that are training. They want to get on the field and we'll make sure, if we have enough for a team, we will field a team.''
The school will need to draft in more players if it is going to get through the campaign, Neilson said.
''We don't want to pull out if we don't have to.
''We are pretty much looking at getting everyone and anyone, who is not playing, to come and make this team up so that we are actually able to play.''
Otago secondary schools rugby council chairman Murray Munro said he was saddened but not surprised Kavanagh was struggling so early in the tournament.
''I suppose it is not too big of a shock to us in that they signalled in the pre-season they were considering dropping down to the under-18 grade,'' Munro said.
''But we've been really keen to work with them as best as we can to keep the tournament as a 10-team competition.''
Munro said most of the other coed schools in the competition were struggling and fielded players from other schools. But Kavanagh did not have an ''obvious'' school in the area it could connect with.
''We are really keen to keep them, maybe as a host for boys out of Kaikorai or Logan Park or Bayfield.
''But there is a very positive side to Kavanagh rugby that I've noted. We've got a colts grade which they weren't able to field a team in last year.
''They've got a team this season and I see that going forward as preparing future first XV players. Teams do have a bad run ... and I'm hopeful this is just one of those bad luck situations.''
Kavanagh was unable to field a cricket team in the Saturday competitions earlier this year.
•King's High School beat Waitaki Boys' High School 32-13 in Oamaru yesterday.
The traditional interschool game doubled as an Otago premier schools fixture.
King's led 13-10 at the break and 18-13 with about six minutes remaining. The home side had defended well but King's scored two late converted tries to stretch the final margin.
