The absence of the Canadian, along with Chinese Shuai Peng, has overshadowed the build-up to the first WTA event in Hong Kong since 1993, which gets under way on Monday.

Bouchard " who was due to be the the top seed for the WTA International event " lost to Ekaterina Makarova in the fourth round at the US Open in a match that saw her require treatment due to the sweltering New York heat.

But Bouchard left it late to inform the Hong Kong Tennis Association of her withdrawal from the upcoming tournament, in a move that has angered the organisation's president, Herbert Chow Siu-lung.

"We are very disappointed that Bouchard is not honouring her commitment even though she lost in the fourth round [of the US Open] and it took her until now to officially inform us that she is not coming," he told the South China Morning Post.

"If Bouchard was injured we could understand and would wish her well. But she is simply tired.

"To say she is tired and cannot turn up because she is fatigued is poor form."

The 20-year-old is ranked eighth in the world and was used heavily to promote the event after an excellent 2014 that saw her reach the Wimbledon final and the last four at the Australian Open and the French Open.

Meanwhile Peng, ranked 39th in the world, will also miss out due to a heat-related illness.

She had to withdraw in the second set of her US Open semi-final against Caroline Wozniacki as a result of the problem.

The Chinese was taken from the court in a wheelchair and in tears after collapsing due to the oppressive American heat.

Another player from China " Zhang Shuai " is likely to assume the top seeding in Bouchard's absence.

The 25-year-old was knocked out in the first round of the US Open by Mona Barthel and will likely face competition from Barbora Zahlavova Strycova, Daniela Hantuchova and Elina Svitolina for the title.