Mayor Peter Chin used his casting vote to ensure a motion to remove $1 million from the Dunedin City Council's budget for the project was lost.
The council signalled Lovelock Ave could be kept open for cyclists and pedestrians, addressing one of the concerns of opponents.
The plan to realign the road, which runs through the Dunedin Botanic Garden, was given one more outing at the annual plan hearing last week.
Garden managers want to realign the avenue to allow more room for the Rhododendron Dell, relocation of propagation houses and administration buildings, and deal with safety issues related to the road, a project supported by the Friends of the Dunedin Botanic Garden.
Many Opoho residents oppose the plan, claiming the new alignment, next to the Northern Cemetery, would be too steep, too frosty in winter and too prone to sun-strike.
A resource consent hearing last year gave the project the go-ahead.
An independent review from Baker Garden Architects, presented to the meeting, concluded realigning the avenue provided the best option regarding the new facilities, improved public access and security.
Cr Kate Wilson moved the $6.5 million cost of the garden's plans be removed from the budget until further options were presented, but it was an amendment to that from Cr Teresa Stevenson - that the $1 million only be removed - that was debated.
Cr Stevenson said she understood what the garden was trying to do, and the concerns of Opoho residents, but other options, such as a "sky bridge" over the road, as raised by submitters, should be explored.
Cr Michael Guest agreed with Cr Stevenson.
Another option may be better than the realignment, he said, which an "overwhelming" number of people in Opoho opposed, with 600 people signing a petition opposing the realignment.
It was not enough to say the resource consent hearing had dealt with the issue, as that hearing did not consider the financial and political aspects of the debate.
Cr Richard Walls said if a new road was to be put through the Town Belt, which Lovelock Ave runs through, "all hell would break loose".
Cr Fliss Butcher said the people of Opoho had felt overwhelmed by the resource consent process, and she would "be the voice of those people today", by voting for the amendment.
Cr Paul Hudson said many people who signed the petition were not from Opoho, and opposition from the suburb was less than some had claimed.
Lovelock Environment Society secretary Dr Antony Wood was surprised the Mayor would push through the decision.
"We have people coming to the council concerned about funding for the Regent Theatre, the museum, the orchestra, the library - there's a whole lot of people queuing up for money.
"And yet, they've decided to spend $1 million on building a road that is not as good as the old one."
Crs Butcher, Cull, Guest, Chris Staynes, Stevenson and Wilson voted for the amendment to remove the funding for the realignment, while Crs Acklin, Brown, Hudson, Walls, Andrew Noone and Mr Chin voted against, with the Mayor's casting vote deciding it was lost.
Friends of the Botanic Garden committee member Jeremy Shearer said he was "very pleased" to hear of the decision.
The Dunedin City Council was dealing with the realignment and new glasshouses, and the Friends of the Botanic Garden would begin fundraising for projects alongside, including a new entrance and tropical glasshouse.
Mr Shearer said those projects would be completed during the next 20 years.
