Wallabies playmaker Quade Cooper has failed in his bid to have a two-match Tri-Nations suspension overturned, with his appeal dismissed on Wednesday.

Following a five-hour hearing, the three SANZAR judicial officers stood by the initial penalty for his dangerous tackle in last weekend's 30-13 win over South Africa.

The Wallabies had hoped that they would at least have Cooper's ban reduced to one match - Saturday's Bledisloe Cup game against New Zealand - which would have made him available for the following week's return encounter in Christchurch.

The decision is a particularly disappointing blow for the New Zealand-born Cooper, who is yet to play a Test against the All Blacks.

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