England captain Alastair Cook, Stuart Broad and Kevin Pietersen will be rested for the opening match of the Ashes tour, a three-day game against the Western Australia Chairman's XI which begins in Perth on Thursday.
Cook has been struggling with a back problem and will sit the game out as a precaution, while Pietersen only arrived in Australia on Sunday having been given compassionate leave following the death of a friend in South Africa.
Broad missed training on Tuesday, also with a back complaint, and he will be assessed ahead of the next warm-up match against Australia A, which gets underway in Hobart on 6 November.
Wicketkeeper Matt Prior will captain the side in the absence of Cook at the WACA but he remained upbeat on Cook and Pietersen's chances of returning to action soon.
"Cookie has a stiff back but rushing him into something is probably not the best idea," he told Sky Sports News.
"Him missing this game is purely precautionary, so I'd be very surprised if he doesn't play the next one.
"KP has jetted around the world and just needs a little bit of rest and recuperation, so he can get into the right time zone, at the very least.
"Giving him a few more days is the best preparation for him."
Prior was also keen to stress the opportunity for batsmen to impress out in the middle in the absence of Cook and Pietersen.
"The top five, top six, have a great opportunity to get in on what looks like a good wicket and score some big runs," he added.
England have loaded their bowling attack with tall, fast bowlers, with Steven Finn, Chris Tremlett and Boyd Rankin all looking to turn in positive performances to boost their chances of selection for the Test team.
"Nets have been good fun at the moment with the big guys steaming in, all playing for their place - the batters have been hopping around a little bit," said Prior.
"It's great to have competition in a team and in a squad, I think that's very healthy. It's not just in the bowlers, it's batters, all-rounders, throughout the team there's a huge amount of competition.
"Everybody's pushing each other very hard and that gets the best out of the final XI chosen."
Watch the Ashes live on Sky Sports this winter, beginning with the opening Test in Brisbane. Coverage begins at 11pm on Sky Sports HD2 on 20 November.
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