A final decision on O'Connell's fitness for the three-Test trip will be made on Friday. He has been battling to overcome a knee injury.
Elsewhere, forwards Chris Henry and Brett Wilkinson both came through Tuesday night's clash against the Barbarians in Gloucester following recent injuries, with uncapped scrum-half Paul Marshall and prop Ronan Loughney also heading to New Zealand.
Loughney will provide front-row cover, including for Leinster prop Mike Ross, who is currently recovering from a hamstring strain.
Scrum-half Isaac Boss and flanker Stephen Ferris had already been sidelined from the tour due to injuries.
Ireland will meet the world champion All Blacks in Auckland on June 9, Christchurch seven days later and then in Hamilton on June 23.
Forwards - R Best (Ulster), S Cronin (Leinster), D Fitzpatrick (Ulster), C Healy (Leinster), J Heaslip (Leinster), C Henry (Ulster), R Loughney (Connacht), K McLaughlin (Leinster), M McCarthy (Connacht), S O'Brien (Leinster), D O'Callaghan (Munster), P O'Mahony (Munster), M Ross (Leinster), D Ryan (Munster), M Sherry (Munster), D Tuohy (Ulster), B Wilkinson (Connacht).