When Tokyo was awarded the rights to the 2020 Olympics in Buenos Aires six years ago, it was hoped Japan's reputation for efficiency and the bid's promise of a "compact games" could ensure a smooth buildup to the event.

Tokyo has mostly delivered on that hope, despite some early teething problems.

Wednesday marks one year until the opening ceremony in the almost-completed National Stadium, and organizers ­believe they are on schedule to deliver a unique Games.

In particular, they point to the unprecedented demand for tickets, with 3.22 million sold during the first domestic sales phase last month, surprising organizers so much that their sales policy has had to be amended.

Over 200,000 people in Japan and abroad have also applied to be volunteers at the Games in a further indication of the excitement building in the country.

Unlike in Rio de Janeiro three years ago, where the Olympics were met with widespread disdain over the use of public funds, the Japanese public have embraced their chance to show off on the world stage.

Local sponsorship revenue has also passed $3 billion, more than any other previous Games, which is necessary as Tokyo 2020 organizers battle rising costs.

The latest budget figures, ­released in December 2018, put the total cost of the Games at $12.6 billion, well above their original estimate at under $7 billion. With all the newly-built and refurbished venues on track to be completed on schedule, organizers may be heading into the final straight with few major headaches but it has not always been plain sailing.

Earlier this year, Tsunekazu Takeda resigned as president of the Japanese Olympic Committee following allegations of suspected corruption related to the 2020 bid.

In 2015, organizers had to scrap the original logo over accusations of plagiarism and the original design for the centerpiece National Stadium was ditched because it was deemed too expensive.

There are also fears over how hot Tokyo may be for athletes and spectators.

A record heatwave in July 2018 killed over a dozen people in Tokyo, with monthly average temperatures reaching more than 30 degrees for the first time since 1998.

Warm, muggy and wet weather will likely greet International Olympic Committee President Thomas Bach in Tokyo on Wednesday for the landmark celebrations that will see the designs for the Games' medals unveiled.