It's A Dundeel will continue his spring campaign in Saturday's Underwood Stakes at Caulfield, in which he will face a top line-up.
Baker said he was still to make It's A Dundeel a certain starter in the Melbourne Cup, the Cox Plate likely to take pride of place as the main aim.
"It's there [the Cup] and I'm sure he'll get the 3200m distance, but it's possible he won't run in it."
Fellow Cambridge galloper Sangster also appears badly off with 54.5kg, but the news was better for Roger James, trainer of Silent Achiever, who was allotted 52.5kg.
Sangster carried 54.5kg to victory in winning the last Auckland Cup, but the class of opposition in that was inferior to what he will meet on November 5.
Dunaden was unplaced in last year's Cup when carrying 0.5kg more than the 58.5kg and will need to end a streak stretching more than 60 years if he is to join Peter Pan (1932-34) as the only multiple winner of the Cup in non-consecutive years.
"Dunaden has been allotted the topweight for the second year running, however, I have reduced his weight by 0.5kg to 58.5kg in recognition of the fact he was beaten almost 10 lengths by Green Moon in last year's race when favourite," Carpenter said.
"While Dunaden enjoys a weight reduction, history still presents a significant challenge as no original topweight has won the Cup since Comic Court in 1950.
"In fact, 20 of them have tried and not one of them has placed so he will rightly claim a place in history if triumphant."
Second in the weights on 57.5kg is the Robert Hickmott-trained, Lloyd Williams-owned defending champion Green Moon, with his high-profile imported stablemate Sea Moon and 2011 runner-up Red Cadeaux both allotted 56.5kg - 1kg more than he carried in 2012.
Last year's runner-up Fiorente, a winner of the Dato Tan Chin Nam Stakes at Moonee Valley on Saturday, rises 1.5kg to 55kg, while the commanding TAB favourite Puissance de Lune has 54.5kg - the weight carried to victory in the past three Cups.
"Fiorente is striving to become the fifth horse to win the Cup a year after running second, with grand mare Empire Rose the last to do it in 1988 when carrying 53.5kg to victory."
Dunaden or Green Moon, if victorious, would become just the sixth multiple winner of the Cup, joining Makybe Diva (2003, 04, 05), Think Big (1974-75), Rain Lover (1968-69), Peter Pan and inaugural winner Archer (1861, 62).
Michael Burn, chairman of the Victoria Racing Club, said this year's 153rd edition represents a significant milestone in the Cup's evolution and that the release of weights sets the scene for another exciting chapter in its history.
"The release of the weights confirms the high quality of this year's entries," Burn said. "We are excited to see such a depth of talent among the entries, both Australian and international, as we mark 20 years since the first international winner of the Cup, Vintage Crop."
