The mayor now supported an independent report on the social costs of the deal to balance the economic benefits.
Mr Brown's concerns about the social effects of a possible 350 to 500 extra poker machines at the casino reflect the concerns of many councillors.
A Herald survey of the 20 councillors found strong opposition from left-leaning councillors to the convention centre for more pokies deal. The only two councillors to support the deal were independents Michael Goudie and Arthur Anae.
A group of eight right-leaning councillors - Chris Fletcher, Cameron Brewer, Calum Penrose, Dick Quax, Des Morrison, Noelene Raffills, George Wood and Sharon Stewart - declined to take part in the survey until Mr Brown gave them more information on the deal.
Deputy Mayor Penny Hulse said: "It is extremely unfortunate that the development of a convention centre that has benefits for the whole of New Zealand had become tied up in a debate around increasing the numbers of pokie machines."
But Mr Goudie said he was "fairly relaxed" about the proposed increase in SkyCity's gaming machines and believed it would have a neutral impact on Auckland.
Councillor Sir John Walker, however, is extremely concerned about the impact of increasing the number of pokies at SkyCity, which return 2.5 per cent of net profit to community groups, and reducing the number of pokies in clubs and bars, which return a minimum of 37.12 per cent of net income to community groups.
The former Olympian - who did not respond to the survey - has said the effect would be to reduce the amount of funding for projects like his John Walker Find Your Field of Dreams, which teaches thousands of young children in South Auckland to swim.
Mr Brown said any decision by the Government to increase the number of pokies at SkyCity should include an assessment of the impact on community projects, such as Sir John's Field of Dreams programme.
Councillor Richard Northey, a former chairman of the Problem Gambling Foundation, said Auckland needed a convention centre but it should be paid for by taxpayers and not by problem gamblers and low income workers from South and West Auckland.
They were the predominant spenders on SkyCity's pokie machines, he said.