With Tuesday marking 500 days to go before Rio stages South America's first ever Olympic Games, the city is straining at the leash to be ready.
In having to overhaul crumbling infrastructure, polluted waters and protests notably over the choice of a nature reserve to host the return of golf to the Games, organizers could almost be forgiven for seeing the undertaking as one mammoth discipline -- a giant obstacle course.
Last April, International Olympic Committee (IOC) Vice-President John Coates slammed preparations as the "worst ever" and warned "the situation is critical on the ground" following several inspection visits.
Organizers responded by creating a taskforce to monitor progress and IOC President Thomas Bach insisted he was "very satisfied" following last month's three-day meeting of the IOC's executive committee in Rio.
But while city mayor Eduardo Paes prepared to mark the 500 days to go milestone by attending drilling of part of the country's largest urban road tunnel, concerns remain over the Games' environmental impact.
Green campaigners and athletes alike have slammed yachting site Guanabara Bay, picturesque but a smelly dumping ground for refuse amid an ongoing struggle to clean up waters which biologists say also risk contamination from superbacteria in adjoining rivers which are resistant to antibiotics.
State authorities admit Rio will struggle to meet an initial pledge to treat 80 percent of the raw sewage which floats into the bay.
The siting of the Olympic golf course in an ecological reserve has also enraged green campaigners, furious at the potential effect on wildlife.
"Cleaning up the bay is an important legacy objective," organizers told AFP in stressing the infrastructural and environmental legacy is "the primary focus" 17 months out from the August 5, 2016 opening.
A total of 7.5 million tickets will go on sale on the official website www.rio2016.com from March 31 with prices ranging from 40 reais ($13) to 1,200 ($383).
Those who have registered online over the past month will from next Tuesday be able to buy. Some two thirds of tickets are expected to be distributed in July and August lotteries.
A full program of test events involving 7,800 athletes was unveiled last week and Tuesday should see the outline competition schedule.
Tuesday was set to see confirmation of Sao Paulo's Corinthians Arena as a football venue, after state authorities indicated they would pay the cost of Games 'overlay' and temporary structures estimated at some $25 million.
"This information has not been confirmed yet but should be shortly," a Corinthians spokeswoman told AFP.
Source: AFP