Olympic and world champion Yuzuru Hanyu revealed Thursday he suffered right ankle tendon and bone injuries in a training fall last month, adding the complaints to the ligament damage that has kept him off the ice since.

A day after the men's figure skating star announced the ligament injury through the Japan Skating Federation, the 23-year-old sparked more concern by saying there is not yet a plan in place for him to return to on-ice training.

"There is also inflammation in my tendon and bone so the speed of recovery will not be quick. It has not been decided when I'll be able to restart training," he said.

Hanyu injured his ankle while attempting a quad lutz during training at the NHK Trophy on Nov. 9, and sat out the Nov. 10-12 competition in Osaka. He also opted out of the Dec. 7-10 Grand Prix Final in Nagoya, where he was aiming for a fifth straight title.

Hanyu injures right-ankle ligament

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The injury casts doubt on his participation in the Dec. 21-24 national championships in Tokyo, which also doubles as a qualifier for the Pyeongchang Olympics. Last year, he withdrew from the national championships due to the flu.

But even if the two-time world champion from Japan misses the nationals, he is practically assured of an Olympic berth based on his No. 1 world ranking and other criteria.

Japan secured three men's figure skating slots and two women's slots for the Pyeongchang Winter Olympics in February.

Hanyu became the first Japanese to strike Olympic gold in men's figure skating in 2014, and is looking to become the first man in 66 years to capture back-to-back Olympic titles. American Dick Button did it last at the 1948 and 1952 Games.