Penrith halfback Nathan Cleary will undergo surgery this week on his foot, which will rule him out of contention for the 2019 end-of-season representative games.
Cleary, who turns 22 in November, has been suffering with an ongoing toe complaint.
The Panthers announced on Wednesday he would have an operation this week to try to fix the problem, ruling him out of forcing his way into the Australian squad after representing NSW over the past two years in the State of Origin arena.
He would be required to wear a moon boot for at least a month and would not be able to resume full training until after the Christmas break.
The length of recovery means he'll miss any chance of being called up for the Australian squad for the Tests against New Zealand and Tonga, or the Prime Minister's XIII against Fiji, or the Kangaroos under-23 side which will play France in Wollongong on October 25.
Cleary would also have been a candidate for Mal Meninga's World Nines side at the RLIF tournament at Bankwest Stadium on October 18-19.
The Panthers also said forwards Jed Cartwright, Wayde Egan and Isaah Yeo had all undergone shoulder surgeries in the past fortnight and were progressing well.