Ashley Beck has been ruled out for six to eight weeks.
Wales and the Ospreys have been dealt a blow after Ashley Beck was ruled out for up to two months.
The centre suffered an ankle injury during his try-scoring cameo against Newport Gwent Dragons on New Year's Eve.
And following further investigation it has been discovered that the 22-year-old has suffered significant ligament damage.
He will subsequently miss the Ospreys crucial Heineken Cup matches with Leicester Tigers and Benetton Treviso and at least the first three fixtures of the RBS 6 Nations, against Ireland, France and Italy.
"Ashley suffered a significant ligament injury to his ankle during the New Year's Eve fixture at Rodney Parade," said Ospreys head of physio.
"We've conducted investigations over the course of the last week to determine the full extent of the ligament damage and plan his rehabilitation effectively.
"Based on the advice received, we are currently treating this as a 6-8 week injury so would expect to see him back in action by the end of February."
Jamie Roberts and Jon Davies remain the tried and tested combination in the Welsh midfield, while the likes of Scott Williams and James Hook offer further options.
Twelve young people have been selected to follow a one year WRU Coach Core apprenticeship programme. Coach Core was set up by the Royal Foundation of the Duke and Duchess of Cambridge and Prince Harry as part of the Olympics legacy in 2012 and the Duke of Cambridge was on hand to meet the apprentices on their first day in the job. The programme has been funded by the Hunter Foundation.
The WRU has launched a campaign to create a long term legacy for Welsh club rugby by highlighting the advantages of volunteering. Rhian Edwards, a volunteer at Seven Sisters, has enjoyed many benefits of her volunteering at a grassroots rugby club including being part of the Rugby World Cup volunteer workforce after being nominated by the WRU - and the WRU is asking for more people to develop their 'Welsh rugby roots'.
Wales head coach Warren Gatland and captain Sam Warburton say their first prioirty on Sunday in the opening game of the World Cup is to win against Uruguay and not get overly concerned with points difference.
With only days to go until the biggest rugby competition in the world begins, rugby fans visiting Cardiff this autumn will be able to enjoy a special display at National Museum Cardiff as part of the celebrations surrounding the Rugby World Cup.