Cardiff Blues have confirmed that centre Owen Williams has suffered a "significant injury to his cervical vertebrae and spinal cord."
The 22-year-old, who has played four times for Wales, was injured playing for Cardiff Blues at the World Cup 10s on Sunday.
The region said that he underwent an operation on Monday to stabilise a fracture and is currently recovering in hospital in Singapore.
His family and Blues staff are with him in hospital, and arrangements are now being made to arrange his safe transfer home "at an appropriate time."
The region and Williams' family have also thanked hundreds of people who have offered messages of support.
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A band of rain pushing in overnight, bringing with it the odd spot of coastal and hill fog, but things should improve by tomorrow.
Local authorities said the move is necessary to "avert the growing number of deaths and increasing harm linked to psychoactive substances".
Sunny and bright spells for most of us this afternoon, feeling pleasantly warm.