The IOC is concerned about unexpected hitches
Organisers of next year's Olympic Games in Athens have been told they cannot afford to lose a single day if they are to be ready for the opening ceremony on 13 August.
An International Olympic Committee (IOC) delegation has just completed a three-day inspection of the main sports venues and other construction work for the games.
The Greek authorities did little to prepare in the first years after winning the Olympics in 1997.
Now those building the sports venues, new public transport systems and other projects are having to work flat out.
Head of the delegation Denis Oswald told the BBC he was concerned that if any unexpected problems cropped up now, the games would be in trouble.
But he said he believed the organisers and workforce did have the stamina to make the final sprint to the finishing line next summer.
"On many projects they worked 24 hours a day," he said.
"What's given us confidence is the fact that in the last six to eight months the timetable [has been] kept, so we don't see any reason why suddenly there would be a delay unless there is something unexpected."
The Olympic Stadium in Athens is still under construction
The IOC was particularly worried about delays to the space-age roof over the main stadium and new transport links around the city.
But they say they have received assurances that the roof will be completed in time to allow proper testing of the venue.
And the Greek Government has pledged to finish a train line connecting the international airport with the city centre as well as a new tram system in the capital.
Security has been another area of concern. Again, the IOC says the security plan is satisfactory and that new equipment for the police force will be delivered soon.