O'Connell, who started the RBS Six Nations as Ireland captain until he suffered a knee injury against France, hobbled off in the second half of the RaboDirect PRO12 victory over Ulster on Saturday.
And following initial assessment from the Munster medical staff it has been decided O'Connell now needs to see a specialist - and the fear is that the talismanic lock may have suffered a reoccurrence of the medial ligament damage in his left knee.
O'Connell spent six weeks on the sidelines following the game against France - and if he has aggravated the problem then it would seem highly unlikely that he would make the trip to New Zealand.
Ireland are due to play three Tests against the All Blacks, starting at Eden Park on June 9. Ireland will then take on the World Cup winners in Christchurch seven days later before completing their tour in Hamilton on June 23.
O'Connell is unlikely to play against this season, with Munster claiming the second rower is 'unlikely' to face the Ospreys in the RaboDirect PRO12 play-off semi-final.
Damien Varley (ankle) is also set to miss that match, although Ronan O'Gara and Ian Keatley are set to be passed fit.
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