Frederic Sinistra, 41, discharged himself from a hospital in Liege after denying he had contracted COVID-19. But Sinistra, who had a 39 win to just 9 loss record, died with complications relating to the virus in the small Belgian city of Ciney just weeks later.
Reports claim the 41-year-old, known as the ‘Undertaker’, told his followers on social media he would treat his symptoms away from the hospital.
Posts shared to Sinistra’s Facebook page showed the kickboxing champion lying in bed at an intensive care ward with an oxygen tube in his nose.
However, Sinistra also posted a video to his 37,000 Facebook followers in which he seemed to have some difficulty breathing.
He added the caption “no time to waste with lazy people”.
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In other posts he called COVID-19 the “little virus” and voiced opposition to the Government’s measures to halt the spread of coronavirus.
Local reports suggest the kickboxer only entered hospital after being forced to do so by his coach Osman Yigin, 50.
Speaking to Belgian news outlet SudInfo, Mr Yigin claimed he told Sinistra he would not train the three-time world champion unless he went to hospital to receive medical attention.
The Belgian athlete remained active online until just days before his death.
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Despite almost 90 percent of Belgians having two doses of the COVID-19 vaccine, the Government introduced fresh measures to halt the spread of the Omicron variant.
Restrictions included restricting public activities and preventing sports fans from watching fixtures at the nation’s stadiums.
Earlier this month, police in Brussels fired water cannons and used teargas to disperse a crowd of around 8,000 anti-lockdown protesters.