The world No 2’s back problem had already forced him to withdraw from the World Tour Finals in Indonesia last week, and the Japanese player has returned home.

His withdrawal from the world championships is a further blow for Momota, who has had a turbulent two years since suffering a career-threatening car crash in Malaysia.

He flopped at the Tokyo Games, and was recently overtaken as world No 1 by Olympic champion Viktor Axelsen.

All Indonesian players who are members of the country’s national association have withdrawn from the championships over virus worries, governing body the Badminton World Federation (BWF) said.

Spain, where the tournament takes place from Dec 12 to 19, is suffering a surge in Covid-19 cases, like much of Europe.

The BWF said in a statement they were “disappointed” with the Indonesian decision and “regret that the withdrawal took place after the draw”.

Two Indonesian players who are not affiliated with the national association will still compete in the mixed doubles, their club confirmed to AFP.

The BWF said a “comprehensive set of safety protocols” is being implemented for the tournament, which will take place inside a bio-secure bubble.