The quartet, consisting of Isaquias Queiroz dos Santos and Erlon da Souza, who together won the C2 1000 metres title at last month's World Championships in Milan, as well as Nivalter Santos and Oliveira Ronilson, are not competing in protest after they reportedly did not receive months of funding earlier this year.

They are also protesting their accommodation for the event at the Army School of Physical Education in Urca, complaining about being awakened in the night by soldiers training.

It is alleged the quartet did not receive eight months of funding from the Brazilian Canoe Federation due to a delay in payments from the National Development Bank.

"We did not stop training, keep working, even without receiving the [support of the] Confederation since February," said Isaquias Queiroz, who also won two golds and a silver in July's Pan American Games.

"One of the causes of our decision is the need to respect athletes.

"It's our way of protest."

But this has been strongly denied by the Federation, with the body's President Joao Tomasini admitting there had been a delay due to a licensing problem but that the athletes have now been paid in full.

All the athletes were paid BRL R$88,000 (£15,000/$23,000/€20,000) during the period in question, the official, also a vice-president of the International Canoe Federation, insisted to UOL Esporte.

The issue is a major blow to the team with less than a year until the Games begin, particularly because the squad is well-positioned to win the first-ever Brazilian medals in the sport.

They are now planning to end their respective seasons, and return to training next month.

Their absence is also a blow for the test event, with a Rio 2016 preview earlier this week highlighting the anticipated presence of both Isaquias Queiroz and da Souza. 

Plenty of leading names are present however for the Aquece Rio International Canoe Sprint Challenge, including other world champions in the form of Germany’s Sebastian Brendel, Denmark’s René Holten Poulsen, Canada’s Mark de Jonge and the Hungarian Gabriela Szabó. 

While most of the attention has focused upon pollution concerns on the picturesque Lagoa Rodrigo de Freitas, swirling conditions and salt water has also presented a challenge so far. 

"[In] this kind of water it's not easy to find the movement," said Hungary's Beijing 2008 C1 1000m champion Attila Vajda.

"This is mixed water, salt and fresh, which is very different to what Europeans are used to paddle."

The unseasonably warm winter in Brazil has also presented an added challenge of weeds in the water, some athletes have reported. 

Action in the test event is set to conclude tomorrow.



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