Penrith have suffered a double blow ahead of the World Club Challenge with star duo Dylan Edwards and Liam Martin to miss the clash with St Helens.
The Panthers decided on Tuesday not to risk the pair ahead of the NRL season, with Edwards managing a minor niggle and Martin out with a shoulder injury.
Both are not expected to be in any doubt for the club's round-one clash with Brisbane, but officials have opted to play it safe with the duo.
Unsung premiership hero Scott Sorensen will also miss Saturday night's match, as Penrith aim to claim their first world title.
Stephen Crichton will play fullback in Edwards' spot, while Zac Hosking will start in the second row for Martin on the right with fellow recruit Luke Garner having won the spot on the left.
Elsewhere, Kalyn Ponga will make his long-awaited return from concussions and a calf injury when he plays five-eighth for Newcastle against Parramatta on Friday.
Lachlan Miller will line up at No.1 against a near full-strength Eels side where J'maine Hopgood has won the role of starting lock.
Brisbane will give Selwyn Cobbo first crack at claiming the No.1 jersey for round one if Reece Walsh is unavailable, with the latter battling a fractured eye socket.
Cobbo will be fullback against a full-strength North Queensland on Saturday night, with Broncos forward Thomas Flegler to sit out with a head injury but in no doubt for round one.
Wests Tigers are also confident hooker Api Koroisau and halfback Luke Brooks will be fit to play in round one, despite missing Sunday's trial against Canberra with calf injuries.
Daine Laurie has kept the fullback jersey for the Tigers, with Charlie Staines on the bench.
Jordan Rapana will also wear the No.1 for the Raiders in the absence of Xavier Savage (jaw), with Harley Smith-Shields winning the battle to replace Rapana on the wing.
South Sydney will run out close to their full-strength side for Saturday's Charity Shield with Izaac Thompson earning the spot on the right wing.
The Dragons will also welcome back their All Stars players for the match, with Moses Mbye to play at five-eighth ahead of the fit-again Jayden Sullivan.
Te Maire Martin has won the battle to partner Shaun Johnson in the halves at the Warriors, with Luke Metcalfe to come off the bench against Melbourne on Sunday.
Charnze Nicoll-Klokstad will play fullback for the Warriors while Nick Meaney is the preferred option at the back for the Storm with Ryan Papenhuyzen out until as late as round eight.
Anthony Milford and Sean O'Sullivan will have first crack as the Dolphins' maiden halves pairing, with young gun Isaiya Katoa to come off the bench against Gold Coast on Sunday.
Euan Aitken has been left on an extended bench for the Dolphins, with Tesi Niu and Brenko Lee the two centres.
The Titans, meanwhile, have confirmed Kieran Foran and Tanah Boyd as their halves, with AJ Brimson at fullback and Jayden Campbell the No.14 with Toby Sexton in the No.20.
Manly and Sydney Roosters have opted to rest halves Daly Cherry-Evans and Luke Keary respectively for their trial on Friday night, with Tom Trbojevic also not back from a hamstring injury.
Hayze Perham will play fullback for Canterbury in their trial against a full-strength Cronulla on Sunday.
