Scarlets are sweating over the fitness of openside flanker James Davies ahead of their next Champions Cup pool clash, against Saracens.
The Welsh region won their opening game at home to Sale but know facing the holders Allianz Park will be another level up on Saturday.
That will be made tougher should flanker Davies not recover from a hamstring injury, with Scarlets currently waiting on news of his scan.
"We're getting a scan done on James' hamstring. He is obviously a big part of our game and we don't want to take any chances on that," head coach Wayne Pivac told the WRU website about his GB 7s star.
"We will know more in terms of the extent of that in the next day or two, but at this stage he is a doubtful starter.
"You want to play in all the big games and push your case, but at the end of the day you want to be 100 percent when you do play because if you are not you get shown up and you don't want that to count against him."