UNDER-18 SIX NATIONS CHAMPIONSHIP:IT IS one of the quirks of this under-18 tournament that the Six Nations Age Grade Committee asks the countries to give at least one start to all squad members.

Clearly there are countries - like England, France and Wales - that, thanks to the depth of their playing resources, are capable of complying with this rule of thumb without seriously damaging their chances.

Usually, Ireland, Scotland and Italy are a different kettle of fish. That theory will be put to the test at Musgrave Park when Ireland run headlong into Scotland.

Coach Peter Melia introduces centres Michael Kelleher and David McSharry into the midfield as a more abrasive partnership, with Diarmuid McCarthy and Michael Allen moved out to the wings, where they might find more room in those one-on-one situations they relish.

Brian Cagney and lock Patrick Butler are promoted to the front five in order to freshen up a pack of forwards that took a pummelling against Wales in the 25-6 defeat on Wednesday.

The Irish did remarkably well to concede only a solitary try against Wales given the total domination of the visitors. It will be up to captain Brian O'Hara to lead his players from the front, where number eight David O'Callaghan and hooker Niall Annett showed up well in the first outing.

Scotland will aim to exploit their advantage in weight and power in the forward exchanges, even though their coach, Grant McKelvey, in what he called "part of the overall development process", has made 11 changes to the side that edged out France 10-8 in their first game.

Captain Stuart McInally, lock Robert Harley, and centres Alex Dunbar and Alex Blair - the latter moved from outhalf - are the quartet retained to dig out a second win in four days.

It reveals a degree of confidence by McKelvey in what is an above-average Scottish squad.

IRELAND U18: N Reid (St Michael's); D McCarthy (Castletroy), M Kelleher (St Munchin's), D McSharry (Templeogue), M Allen (Methodist); L Marshall (Ballymena Academy), D O'Driscoll (PBC, Cork); B Cagney (PBC, Cork), N Annett (Methodist), J O'Connell (Clongowes Wood); P Butler (Rockwell), B Marshall (St Andrew's); D Ryan (Gonzaga), B O'Hara (PBC, Cork, capt), D O'Callaghan (Midleton).

SCOTLAND U18: T Brown; R Drummond, A Blair, A Dunbar, S McKenzie; R Aitken, A Black; L Pettie, A Walker, N Little; C Connor, R Harley; M Maltman, M Fedo, S McInally (capt).

ALSO PLAYING: England v France (CIT, 2.30), Italy v Wales (Mardyke, 2.30).