Walker was due to captain the Indigenous All Stars against the Maori All Stars on Friday night in Townsville,but told officials on Saturday he had to withdraw after picking up an injury at training.
Jack Wighton has opened up on his move from Canberra to South Sydney ahead of the NRL season and a potential State of Origin return.
Latrell Mitchell,Josh Addo-Carr and Nicho Hynes are in contention to take over as skipper.
Indigenous coach Ronnie Griffiths confirmed Walker had a calf injury,understood to be a grade-one strain,and said the Souths star was devastated when he delivered the news.
“I spoke to him before I boarded a flight from Brisbane;he told me he did his calf and was out,” Griffiths said. “It’s a massive blow for us and a massive blow for Cody because he’s a player who makes himself available every year. He loves the game and that passion and leadership exudes out of him when he plays.”
Griffiths spent much of Saturday afternoon trying to find a replacement for Walker,who also helped as an assistant coach last year. Hynes and Braydon Trindall will be the starting halves in Townsville.
Cody Walker has been ruled out of Friday night’s All Stars game.Getty
The first of the trials kicks off next weekend and Griffiths hopes several players who were ruled ineligible for the All Stars during the week do not feature for their clubs.
Souths held an opposed session at Maroubra,which essentially doubled as their unofficial first trial. They will start their fringe players against Manly on Sunday and have only next weekend’s Charity Shield against St George Illawarra to finalise their combinations before flying to the US.
After playing Manly in Las Vegas,the Rabbitohs have a relatively tight turnaround given the travel involved,with their round-two match in the Thursday night slot in Brisbane against the Broncos.
Walker’s latest injury is not the same calf he injured before Christmas.
Should the 34-year-old struggle to be fit for round one,Souths might need to turn to Dean Hawkins to partner Lachlan Ilias,or even move Mitchell from fullback and drop Alex Johnston to No.1.
Jack Wighton could have slotted into the halves,but he is suspended until round three.
Souths confirmed Walker will have scans on Sunday morning. A grade-one strain usually involves two to three weeks on the sidelines.
Rated one of the premiership heavyweights,Souths were still reeling from the news earlier in the week that strike centre Campbell Graham could be out for up to six months after requiring fresh surgery to his sternum.
Meanwhile,Manly’s Josh Aloiai and Corey Waddell are late scratchings from Sunday’s game against Souths,with Karl Lawton and Aaron Woods to skipper the Sea Eagles.
Aloiai pulled up with calf tightness on Thursday while Waddell also suffered a knock. Neither player is expected to be in doubt for the Vegas game.
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