Newport and Wales centre Andy Marinos is fighting to recover from deep vein thrombosis.
The 30-year-old has the life threatening condition and only early detection has stopped it from claiming his leg.
And now Marinos faces a race against time to recover for the World Cup in Australia this October.
"I'm hoping to be play at least a month and a half of the season and try and stake a claim to get into the World Cup squad, but time is not on my side," admitted Marinos.
Marinos had already been ruled out of this year's Six Nations campaign after suffering damaged ligaments in his foot earlier in the season.
And despite his confidence that he will eventually return to full fitness Marinos has admitted that his leg could never fully recover from the condition also known as, "economy class syndrome," due to its association with long-distance travel.
He said: "Once you've damaged an artery in the leg it's never going to be the same again.
"I had anticipated being back in the middle of March but this is obviously a massive set back."
Marinos first made his Wales debut against Ireland in last season's Six Nations championship and was the highlight of an otherwise disappointing campaign for the Principality.
But even if he does recover from DVT his hopes to travel to Australia could be skuppered due to the connections between the condition and air travel.
And a 60 hour round-trip to Australia for the World Cup is unlikely to be beneficial for Marinos' leg.
However, the South African born star is still positive that he will be able to travel
"I've got to be sensible and manage it correctly on any long haul flights, said Marinos. "I've been advised to take some form of blood thinner to help me out."
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