Campbell's Thomas Horner scored 15 points

Wallace finally got their name on the scoresheet when scrum-half Thomas Shorten banged over a penalty into the freshening wind.

That, however, was matched by Horner's second effort leaving Campbell 23-3 ahead at the break.

Wallace continued their onslaught close to the fringes after the break, but still found Campbell a hard act to break down.

They finally did achieve their goal in the 55th minute with number 8 Chris Henry barging his way over from a short penalty.

That signalled an all-out assault on Campbell who began to tire in the final stages.

However, the 1999 winners had one last effort up their sleeve with their fourth try two minutes from time.

Full-back Johnny Cartmill made a dash up the left wing only to be brought down by covering left wing Iain Semple.

However, from an adjudged high tackle Campbell took a quick penalty and flanker Glenn Moore charged in under the posts for Horner to convert.

Campbell will now face the winners of Thurday's second semi-final at Ravenhill between hot favourites Methody and Bangor Grammar (1430GMT).

Campbell College: J Cartmill; J Moutray; R Rea, P McCausland, B Elliott; T Horner, N Wallace; R Kelso, C Thallon, A Stewart, M Willis, J Andress, W Uzoigwe, G Moore, N McComb, capt.

Scorers: Tries: Moutray, Elliott, Horner, Moore; Pens: Horner (2); Cons: Horner (2).

Wallace High: G Beattie; A Savage; L Jones, A Currie, I Semple; M McCormick, T Shorten; S Trimble, D Morrison, A Megarry, J Moore, capt, D Dawson, M Hill, T Lee, C Henry.

Scorers: Try: Henry; Pens: Shorten.

Referee: S McDowell (Ulster Branch)