Murphy blow for Ireland
The 25-year-old Spain-born flank – who scored the first try in their 40-29 win over the All Blacks in Chicago last Saturday to end a 28 Test and 111-year hoodoo – injured the cruciate ligament in his left knee in the first-half.
The most optimistic prognosis of a return to action is six months, with the worst case scenario nine months.
Ireland coach Joe Schmidt has added six players to the original squad he named a fortnight ago as they build towards playing Canada on Saturday at Lansdowne Road.
They follow it with a second Test against the All Blacks on November 19 and round off their programme with a match against 2015 World Cup finalists Australia on the 26th.
Niyi Adeolokun, Tiernan O'Halloran (Connacht), Dave Kilcoyne, Jack O'Donoghue, Darren Sweetnam (Munster) and Dan Leavy (Leinster) have joined the squad.
There are nine uncapped players in the extended 39 man squad.
Ireland squad: Niyi Adeolukun (Connacht), Finlay Bealham (Connacht), Rory Best (Ulster/captain), Joey Carbery (Leinster), Sean Cronin (Leinster), Ultan Dillane (Connacht), Keith Earls (Munster), Tadgh Furlong (Leinster), Craig Gilroy (Ulster), Cian Healy (Leinster), Jamie Heaslip (Leinster), Iain Henderson (Ulster), Robbie Henshaw (Leinster), Billy Holland (Munster), Paddy Jackson (Ulster), Rob Kearney (Leinster), Dave Kilcoyne (Munster), Dan Leavy (Leinster), Kieran Marmion (Connacht), Luke Marshall (Ulster), Jack McGrath (Leinster), Luke McGrath (Leinster), Conor Murray (Munster), Sean O'Brien (Leinster), Jack O'Donoghue (Munster), Tiernan O'Halloran (Connacht), Peter O'Mahony (Munster), Jared Payne (Ulster), Garry Ringrose (Leinster), Donnacha Ryan (Munster), John Ryan (Munster), Jonathan Sexton (Leinster), CJ Stander (Munster), Darren Sweetnam (Munster), Devin Toner (Leinster), James Tracy (Leinster), Andrew Trimble (Ulster), Josh van der Flier (Leinster), Simon Zebo (Munster).