Garry Ringrose will make his first senior start at inside centre to solve injury-hit Ireland’s midfield dilemma against Australia in Dublin on Saturday.
The 21-year-old has not started a game at 12 since turning out for Leinster’s under-20s last season but acquitted himself admirably in the role off the bench against New Zealand last weekend.
Robbie Henshaw’s absence through concussion and Johnny Sexton’s hamstring problem has forced Ireland into several midfield reshuffles to take on the Wallabies.
Paddy Jackson slots in at fly-half with British and Irish Lions fly-half Sexton sidelined, while Rob Kearney and CJ Stander have overcome concussion issues to start.
Ireland had drafted Ulster centre Stuart Olding into their squad in midweek while releasing midfielder Luke Marshall back to the Belfast province.
But Ireland boss Joe Schmidt has opted to give highly-rated Ringrose his head at inside centre, even though he has not even started a PRO12 match for Leinster in the role.
Ringrose coped well enough at 12 off the bench to replace the concussed Henshaw in Ireland’s 21-9 loss to the All Blacks in Dublin last weekend.
Ireland lost their midfield attacking shape however, with Ringrose in unfamiliar territory at inside centre and Paddy Jackson also thrust into action prematurely after Sexton’s hamstring problem.
Keith Earls has stepped up to start on the wing, with Simon Zebo dropping to the bench after missing training in the early part of the week.
Captain Rory Best will win his 100th Test cap, leading the Ireland side from hooker.
IRELAND: R Kearney (Leinster), A Trimble, J Payne (both Ulster), G Ringrose (Leinster), K Earls (Munster), P Jackson (Ulster), C Murray (Munster), J McGrath (Leinster), R Best (Ulster, capt), T Furlong (Leinster), I Henderson (Ulster), D Toner (Leinster), CJ Stander (Munster), S O’Brien, J Heaslip (both Leinster).
Replacements: S Cronin, C Healy (both Leinster), F Bealham, U Dillane (both Connacht), J Van der Flier (Leinster), K Marmion (Connacht), J Carbery (Leinster), S Zebo (Munster).