All Blacks fullback Leon MacDonald has been ruled out of Saturday's Tri-Nations rugby rematch against Australia, adding more pressure on coach Graham Henry as he attempts to even the ledger.

New Zealand team doctor Deb Robinson said MacDonald had ongoing concussion symptoms after suffering a blow to the head during the 30-28 loss to South Africa on July 12.

He was rested for last week's Test against the Wallabies, in which the All Blacks were comprehensively outplayed 34-19.

Although called back into the side for next weekend's match, MacDonald continued to be fatigued in training and at team meetings, signs he was still feeling the effects of the blow, Robinson said.

There was no immediate word on a replacement, but the selectors may revert to last week's fullback Mils Muliaina who had been moved to the wing to make way for MacDonald.

The All Blacks are desperate to win on Saturday to keep alive their hopes of defending the Tri-Nations title and to restore credibility after admitting they were out-smarted last week by Wallabies coach Robbie Deans.

Chances are that Henry will cover MacDonald's withdrawal by recalling either Anthony Tuitavake or Rudi Wulf to the wing, and shifting Mils Muliaina from wing to fullback, where he played last week.

365