The 70-times capped Geordan Murphy will line out at full-back with Tommy Bowe and Keith Earls, two more tournament newcomers, completing the back-three.
Brian O'Driscoll and Gordon D'Arcy, who has recovered from a calf strain to win his 60th cap, form their regular centre partnership.
O'Driscoll is hoping to guide Ireland to an opening win in New Zealand, which would be his 50th victory in 77 Tests as team captain. He is also the first Irish player to play in four World Cups.
Tom Court replaces the injured Cian Healy (eye) at loosehead prop, joining Rory Best and Mike Ross in the front row, and Donncha O'Callaghan and Paul O'Connell link up once again in the second row.
The three starters in the back row are all World Cup debutants. Stephen Ferris and Jamie Heaslip have been retained from the last warm-up game, with openside flanker Shane Jennings coming in to make his first tournament start for Ireland.
Tony Buckley and Donnacha Ryan are standing by to make their World Cup bows as replacements. They are part of a bench which boasts a total of 305 caps.
IRELAND Team & Replacements (v USA, 2011 Rugby World Cup Pool C, Stadium Taranaki, Sunday, September 11, kick-off 6pm local time/7am Irish time):
15 - Geordan Murphy (Leicester Tigers)
14 - Tommy Bowe (Ospreys) *
13 - Brian O'Driscoll (UCD/Leinster) (capt)
12 - Gordon D'Arcy (Lansdowne/Leinster)
11 - Keith Earls (Young Munster/Munster) *
10 - Jonathan Sexton (St. Mary's College/Leinster) *
16 - Jerry Flannery (Shannon/Munster)
17 - Tony Buckley (Sale Sharks)*
18 - Donnacha Ryan (Shannon/Munster)*
19 - Denis Leamy (Cork Constitution/Munster)
20 - Eoin Reddan (Lansdowne/Leinster)
21 - Ronan O'Gara (Cork Constitution/Munster)
22 - Andrew Trimble (Ballymena/Ulster)
* Rugby World Cup debutant
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