Featherstone Rovers prop Andy Bostock was taken to hospital for an x-ray after being taken off in the second-half of Sunday’s pre-season game at Castleford Tigers.
Bostock sustained a jaw injury in a match Castleford won 42-28 after they led 30-0 at half-time.
Featherstone’s new signing Matt Wildie was also injured but it wasn’t serious.
Rovers coach Jon Sharp said: “It looks like Wildie has suffered concussion but he should be fine. We’ve more concerns with Bostock at this stage.
“Bostock has gone to hospital for an x-ray on a jaw injury. It’s too early to say whether it’s broken or not.
“That’s one of the disappointments of friendles and one of the things that always worries you a little bit. You want to try to get through games like this unscathed.”