Oram injured his left knee while fielding in New Zealand's two-wicket win in Napier, and a scan revealed a partial tear of the patella tendon, which gives him no chance of returning at any stage of the five-match series which the hosts lead 1-0.
"It is expected that Jacob will recover in three to four weeks, however he will be out for the balance of the Australian series," stuff.co.nz Dave Currie, New Zealand team manager, as saying.
The Black Caps are likely to miss Vettori, as he has failed to recuperate from the chronic neck injury, which kept him out of the opening game as well.
Currie said Vettori's was still troubling him, and he would test it at training on Friday.
"He's not 100 per cent certain (to play). The neck was a bit stiff. We're certainly hopeful and he's hopeful, but again we'll get through today and get more treatment and see how he wakes up in the morning," Currie said.
Meanwhile, fast bowler Michael Mason has been summoned to Auckland to cover up for the injured stars.
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