The Ospreys are sweating on the fitness of star duo Ashley Beck and Justin Tipuric ahead of the crunch Heineken Cup clash with Leicester Tigers.
The Swansea-based region must maul the Tigers to keep their European hopes alive but could be without the international pair.
Beck is unlikely to recover from an ankle injury in time and Tipuric's chances are rated at 50/50.
"Tips is doing some rehab and is 50-50, but we are waiting on some extra information on Ashley Beck, who is a real doubt," said Ospreys head coach Steve Tandy.
"Tips has been huge for us, Becky, too. It something we've had to get used to this season, with senior players missing, people like Ian Evans, Alun Wyn Jones, Aaron Jarvis and Hanno Dirksen.
"If we lose Beck and Tips it will be a huge task for us, especially given the limited squad we have. But it's something we have to prepare for and we are going to give it a right old go."
Tandy was more hopeful of having Tipuric available for selection but he insists he will take no risks despite the magnitude of the game.
"There's always that temptation but we won't put the group before the player," said Tandy.
"If he's not right, he's not right. There are educated risks in what we are doing, but I need to sit down with the physio and see where they are come Friday.
Tom Issacs is set to fill the void left by Beck and Sam Lewis is a front-runner to start if Tipuric fails to recover.
And Tandy insists the Ospreys are confident of the duo coming in and producing the goods.
"We have no issues with TI (Isaacs) starting at 13 this weekend. He did really well for us there against the Scarlets earlier in the season.
"We'll weigh things up in the back-row, but we have a boy in Sam who's outstanding every time he wears the shirt.
"He was out on his feet at the end of the Zebre game, especially after his performance against the Dragons. He is developing all the time.
"You find out more about people on these big occasions and we are keen to develop from within. I know if Sam has to step into the role he won't let us down."
Wales Head Coach Rob Howley talks to WRU TV's Sebastian Barrett about the 36-man squad he has just named for the forthcoming Under Armour series, which includes two uncapped players, Ospreys duo Sam Davies and Rory Thornton.
Head coach Rowland Phillips is deligthed he can now call BT Sport Cardiff Arms Park home for his Wales Women's side, who launch their international season next month with games against Scotland and UK Armed Forces in the heart of the capital city.
Wales Sevens star Sam Cross has put his home town club of Brynmawr on the map after winning a silver medal at the Rio Olympics with Team GB. His club have now honoured him by naming their players bar after him, as WRU TV discovered at the official launch, recently.
One of the newest members of the Principality Premiership, Bargoed admit it's proving to be a steep learning curve at the highest level, but are determined to become a force to be reckoned with. WRU TV visited the club last weekend when they took on Llanelli.
Table-topping Aberavon travel to north Wales to tackle RGC 1404 as both teams defend unbeaten starts to the season in the Principality Premiership. WRU TV's Graeme Gillespie visited the Wizards to see how their preparations were going for the game of the weekend.
The Half a Game initiative is currently sweeping across Wales and proving a major success. The scheme aims to give every young player at least half a game every weekend. WRU TV recently visited a festival in Narberth where clubs have fully embraced the initiative.
Both Bargoed and Swansea were seeking their first win of the Principality Premiership season this afternoon. It proved a fruitful day for the hosts - not only did they win, but Bargoed claimed a try bonus point.
Cardiff managed to keep their unbeaten record at home intact, but only just as Bridgend made them work extremely hard before the Blue and Blacks secured a hard fought Principality Premiership win at the BT Sport Arms Park last night.
Former Wales back row Andy Powell gives a guided tour of The Wern, home of Merthyr RFC, who are determined to prove a lot of people wrong and make their mark in their first season in the Principality Premiership.