Lee Byrne will spend time in an oxygen tent in a last-ditch attempt to shake off an ankle problem in time for Sunday's Heineken Cup quarter-final.
Byrne picked up the injury in the Six Nations against Ireland though is no longer wearing a protective boot.
He said: "I'll give anything a try to make that game so I'm having a few sessions in the tent. It's different but hopefully it will help."
Byrne hopes to rubber stamp his place as front-runner for the British Lions No15 jersey by helping the Ospreys to their first European semi-final.
Ian Gough also looks set to recover in time but Gavin Henson it out with his third injury this season.
Scott Johnson clocked on at the Ospreys on Monday but coach Sean Holley insists he is still in charge for Europe.
Former Wales boss Johnson arrived at the Liberty Stadium at the weekend to take up his post as director of coaching after a year in charge of USA Eagles.
But Holley will call all the shots ahead of the crunch cup tie in Limerick. He said: "Scott will take some time to soak up the environment and see what's going on before he steps in. I doubt he will have any input this week ahead of Munster."
He added: "Scott will be instrumental at the Ospreys. He will bring a new voice and fresh approach as well as his confidence."
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.
Geraint John has taken up the new role of WRU elite coach development manager having arrived in Wales last week. WRU TV caught up with him at the WRU rugby department's strategy day at the Millennium Stadium.
The entire Welsh Rugby Union Rugby Department gathered at the Millennium Stadium earlier this week where WRU Head of Rugby Josh Lewsey looked back on a year where structural and strategic changes have seen significant progress made
The Welsh Rugby Union has released a specially produced video to spearhead a new campaign to help promote the values of rugby union. The video, entitled Let us Play underpins the WRU rugby department's philosophy - to engage, transfer and retain players, coaches and referees.