Tony Pulis told the official web-site: "We've had some bad news with John because his knee problem is worse than we first thought.
Eustace needs Op
"We're going to have to give him another couple of weeks and it could need a small operation which would mean that his season is over.
"There could be some floating bone or floating cartilage in his knee which was picked up on a scan the other day.
"It's been a disappointing season for him and for the club because if he's fit he's as good as any midfielder in the league and it's been a massive blow to lose him this year.
"There could be some floating bone or floating cartilage in his knee which was picked up on a scan the other day.
"It's been a disappointing season for him and for the club because if he's fit he's as good as any midfielder in the league and it's been a massive blow to lose him this year.