Leinster's inexperienced fly-half Joey Carbery could make his Test debut when Ireland attempt to stop New Zealand extending their record match-winning streak in Chicago on Saturday.

Carbery has just nine senior Leinster appearances to his name and turns 21 on November 1, but could now take a seat on Ireland's bench for Saturday's autumn Test opener against the double world champions.

Ulster's Paddy Jackson will miss the USA trip due to personal reasons, leaving prodigious talent Carbery the most likely understudy to Johnny Sexton.

Ireland must also bid to deny New Zealand a 19th consecutive victory without influential forwards Sean O'Brien, Iain Henderson and Peter O'Mahony.

"Players returning to full fitness Sean O'Brien, Iain Henderson and Peter O'Mahony along with Paddy Jackson, unavailable due to personal reasons, will not make the trip to Chicago," the Irish Rugby Football Union (IRFU) confirmed in a statement.

Sexton should start Saturday's Soldier Field clash, with Leinster team-mate Carbery now likely to take a seat on the bench in Ulster playmaker Jackson's absence.

Carbery has been promoted to Ireland's senior squad for the autumn series ahead of Ian Madigan, now plying his trade in Bordeaux.

Ireland would ideally have aimed to ease the Leinster academy graduate's transition, but his form in the Guinness PRO12 suggests he boasts the requisite skills to cope in the Test arena.

Leinster flanker O'Brien has only just returned from long-term hamstring trouble, and has been deemed not quite ready for Test rugby.

Ireland will hope the combative loose-forward will be available for selection by the time they face New Zealand again, in Dublin on November 19.

Peter O'Mahony has recently beaten the knee ligament problem that ended his World Cup 2015 campaign prematurely in the 24-9 pool stage victory over France.

As with O'Brien, Ireland are taking few risks with the Munster captain in the hope the 27-year-old can be at full tilt by the time New Zealand pitch up in Dublin.

Powerful back-five forward Henderson suffered a shoulder injury in Ulster's 19-18 Champions Cup victory over Exeter Chiefs on October 22.

Ireland remain hopeful the 24-year-old can make a quick recovery to play a meaningful part in what will be another gruelling November series.

IRELAND'S 27-man squad to face New Zealand in Chicago on Saturday: F Bealham (Connacht), R Best (capt), J Carbery, S Cronin (both Leinster), U Dillane (Connacht), T Furlong (Leinster), C Gilroy (Ulster) C Healy, J Heaslip, R Henshaw (all Leinster), B Holland (Munster), R Kearney (Leinster), K Marmion (Connacht), J McGrath, L McGrath, J Murphy (all Leinster), C Murray (Munster), J Payne (Ulster), G Ringrose (Leinster), D Ryan, J Ryan (both Munster), J Sexton (Leinster), CJ Stander (Munster), D Toner (Leinster), A Trimble (Ulster), J Van der Flier (Leinster), S Zebo (Munster).

PA Media