Widnes back rower Danny Tickle will be unavailable for around a month, as he is set to undergo surgery on a groin injury.
Tickle played 30 games out of 32 last season for the Vikings, and has not missed a game so far in 2015.
Now, though, it looks unlikely that he will be back in action until after Easter.
“Danny has been carrying the injury for the last few weeks,” Widnes coach Denis Betts revealed to reporters.
“It’s been affecting the way he’s performed.
“He’s toughed it out but we need to look at him and do what’s best for him.
“It’s a huge blow for us because he’s been fantastic for the last two years but we’ve been nurturing him along and now it’s time to bite the bullet.”
“Patrick has got some concussion issues at the moment. We’re just being really smart with him,” Betts added.
“He got hit on the head in a game and had a bit of delayed concussion.
“His symptons have kept resurfacing when he’s been putting the effort into training so, under medical advice, we’ve had to step him back and take our time with him.
“At the moment he’s in some kind of sabbatical. He’s sat at home waiting for his symptons to calm down. We’re monitoring him almost daily.
“When he’s ready to go, he’ll have to go through six or seven days of training before he’s allowed to be up for selection. That’s in the medical people’s hands.”