by Brendan Cole
Declan Kidney is set to name Paddy Jackson in the starting line-up and Ronan O'Gara on the bench when he reveals his team to face Scotland at lunchtime today.
The Ireland head coach is also expected to name Ulster duo Luke Marshall and Tom Court in a starting XV that will be radically different to the one which faced England in the second round of the Championship.
The changes are required because Jonathan Sexton and Gordon D'Arcy are unavailable due to hamstring and foot injuries respectively, while Cian Healy is suspended.
But it was widely expected that Kidney would back veteran out-half Ronan O'Gara to replace Sexton despite doubts about his form, but 21-year-old Ulster star Jackson now looks set to get the nod in the position.
If his selection is confirmed, Court will leapfrog David Kilcoyne and come straight into the starting XV after missing out on a place among the replacements in Ireland's opening two matches.
Marshall, 21, returned from a fractured finger suffered in early January in Ulster's win over Zebre in the RaboDirect Pro12 at the weekend and has reportedly shaken off dead legs suffered in that match.
Kidney must also make changes on the wing and in the second row, with Simon Zebo ruled out for the remainder of the Championship due to a broken metatarsal and Mike McCarthy unavailable for this match due to a knee ligament injury.
Keith Earls is in pole position to claim the spot on the wing having replaced Zebo 10 minutes into Ireland's defeat to England in round two. Donncha O'Callaghan is likely to replace McCarthy in the second row.
With back-row substitute Chris Henry also unavailable due to a leg injury picked up against Zebre, Ireland must also name at least three new substitutes.
Live RBS 6 Nations coverage on RTÉ Two from 2pm on Saturday 23 February and 1.15pm on Sunday 24 February (Scotland v Ireland). Live streaming Ireland only.
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