Five members of Sydney Roosters' 2019 premiership side remain as Trent Robinson targets a fourth title, but Connor Watson will miss Sunday's grand final.
Watson suffered a head knock in the preliminary-final win over the Dolphins and was withdrawn on Friday after seeing specialists, despite responding well.
NRL rules prevent players returning within 11 days, making Watson the first player ruled out of a grand final under concussion protocols introduced in 2023.
Calls for a two-week break before the decider grew after his exclusion; the extra time could have allowed him to play his final Roosters game before joining St George Illawarra.
Robinson rejected the proposed change. "These are unfortunate things that happen, but we have protocols for a reason," he said at Accor Stadium on Saturday.
"I'm more for the week off before the finals than I am before the grand final."
He added: "I feel like momentum's built throughout the final series and the attrition part of it is a part of the game."
Hooker Benaiah Ioelu will replace Watson in the Roosters' 19-man squad.
Walker, 24, and veteran five-eighth Daly Cherry-Evans will partner in the halves as the Roosters pursue their first premiership in seven years.