Very little is known about the nature or extent of Owen Williams' injury, sustained whilst playing for Cardiff Blues against Asia Pacific Dragons in the World Club 10s on Sunday.
The Blues released a statement yesterday, saying: "Owen Williams is to remain in hospital in Singapore after sustaining an injury at the World Club 10s. Cardiff Blues will issue further updates when they are available."
Blues teammate Macauley Cook also tweeted yesterday to say he was at the hospital with Williams, waiting for his family to arrive.
The WRU said 22-year-old Williams has not travelled home with the rest of the Blues squad.
More top news
Described as the 'hidden disability', autism affects how people perceive the world and interact with others.
A driver from Newport has been handed a 21 month sentence behind bars after wracking up a number of driving offences.
A man whose shoe print was found at the scene of a sex crime has been jailed for 10 years.