Kangaroos star half Cameron Munster is reportedly in doubt for Australia's Pacific Cup final warm-up against New Zealand on Saturday evening in Melbourne.

Australia and New Zealand have both beaten Samoa over the opening fortnight of the tri-series, meaning they will contest the final in Hamilton on November 4.

In the meantime, though, the two teams must play their tri-series game in Melbourne on Saturday. The Kangaroos have already elected to make plenty of changes from the opening match in Townsville against Samoa, but will now potentially also play without Cameron Munster.

NRL.com are reporting that Munster failed to train on Wednesday, instead waiting back at the team hotel at Albury where the Kangaroos are in camp this week before making the trek to Melbourne for Saturday's clash.

It's understood that rather than being injured, Munster has instead fallen ill.

The star Storm half, who piloted Queensland to State of Origin victory over the Blues this year and played a significant hand in taking his club side to a preliminary final, was a star for the Kangaroos in their opening tri-series clash against Samoa.

If Munster is ruled out, Nicho Hynes, who has been named to make his debut off the Kangaroos' bench, will move into the halves freeing up a spot for another forward on the pine.

All of Liam Martin, Tino Fa'asuamaleaui and Payne Haas, who played in the opening clash against Samoa, have been rested for Saturday's clash and are instead among the reserves.

Brisbane Broncos winger Selwyn Cobbo is in the same boat, although it's unlikely coach Mal Meninga will go for another back to match up with the Kiwis enormous group of forwards.

The Kangaroos and Kiwis clash on Saturday evening at AAMI Park, with kick-off set for 8:10pm (AEDT).