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."
Despite drawing with Ireland in the opening round of the RBS 6 Nations, Wales defence coach Shaun Edwards believes the championship 'is still in our hands' as he prepares his side to face Scotland at Principality Stadium tomorrow.
Meet the members of the WRU's inaugural Youth Board - after an online selection process which saw a host of high calibre candidates submit video applications the WRU has made its first 15 appointments.The board is made up of individuals aged between 16 and 21, and will meet for the first time at Principality Stadium on Monday 15th February.
The Wales Women's team headed to Dare Valley Country Park on a team bonding exercise as the entire squad got together for the very first time in preparation for this season's Six Nations championship which kicks off on Saturday with a clash against defending champions Ireland, in Donnybrook.
Wales Head Coach Warren Gatland discusses his team selection for the opening round of the RBS 6 Nations where he leads his side against Ireland, on Sunday. As WRU TV's Luke Brodley discovers, Gatland is fully aware of the challenges the defending champions pose