Penrith prop Sam McKendry has gone under the knife for his second knee reconstruction in less than a year.
The 27-year-old Kiwi international injured his knee in a trial match against Parramatta in February - his first game back since rupturing his ACL last July.
Panthers coach Anthony Griffin said the club tried to avoid surgery but were left with no option but to send him to hospital last Thursday.
"We went down the track of trying to rehabilitate him but it got to a point where it wasn't going to work," Griffin said after Penrith's 28-6 loss to Melbourne at AAMI Park on Saturday.
In some more positive news for the Panthers, young Rawene forward James Fisher-Harris is likely to return from a fractured cheekbone for next Friday night's clash with South Sydney.
Second-rower Bryce Cartwright could also be available as he recovers from bone bruising.
"James will be right next week and Bryce is pretty close so if not next week than the week after we'll be expecting him to play," Griffin said.
The Panthers will be hoping Fisher-Harris can quickly find his form from last season as they currently have a two-win, three-loss record.
They will be able to call on the services of a top young Kiwi as Dallin Watene-Zelezniak has signed a new three-year deal with the club.
The contract extension means the 21-year-old Kiwi international will remain with the Panthers until at least the end of the 2020 season.
"The decision to re-sign with the Panthers was an easy one to make," Watene-Zelezniak said.
"Penrith has been my home since I was a kid and it has always been my dream to play first grade for the Panthers.
"I consider myself very lucky to be able to live that dream at such a fantastic club."
- AAP.