Third Ashes Test: Australia v England
Venue: Melbourne CG Dates: 16-20 December Start time: 0230 GMT
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Harris was the pick of the home side's bowlers in Adelaide
Australia paceman Ryan Harris has been declared fit for the third Ashes Test which starts in Perth on 16 December.
The 31-year-old was in doubt for the game after appearing to injure his shoulder while bowling in the second Test defeat in Adelaide.
But a scan has cleared him of any serious damage and he is now able to bowl unrestricted.
Australia are due to name their squad on Friday after the opening day of Victoria's match against England.
The decision to name their squad so early was criticised by Victoria coach Greg Shipperd.
He believes several of his players, especially batsmen Cameron White and David Hussey, would be in with a chance of staking a claim for selections during the three-day game against the tourists in Melbourne.
"Against New South Wales, full-strength, David Hussey scored a blistering hundred and Cameron White, all he could do was score a hundred against England down in Tasmania," Shipperd told Australian radio station Sport 927.
"Hussey, like the incumbent number six [Marcus North] bowls some off spin and Cameron White offers a leadership for the future option, so there's some good reasons why you would consider them strongly."
Harris took 2-84 from his 29 overs in England's only innings in Adelaide.
It was his first Test match in nine months after he suffered a knee injury in a one-day international against England in July.
His availability is a boost for the under-pressure Australian side who are already missing opener Simon Katich with an Achilles tendon injury and trailing 1-0 in the five-match series after two games.
Phil Hughes, who was backed by captain Ricky Ponting as the favourite to take over from Katich, says he is ready to take on England's attack in Perth.
Hughes struggled against England's short-pitched bowling in the 2009 Ashes series and was dropped after two Tests.
He scored two and 82 against an England XI in a tour match in Hobart in November, but was dismissed cheaply playing for state side New South Wales this week.
"To get that support from Ricky is fantastic, obviously [he's] the Australian captain and he's been around for so long," Hughes told Australian television.
"I know mentally and technically I'm ready. I just can't wait to see who [the selectors] pick."
But England captain Andrew Strauss has already publicly doubted Hughes's ability against his bowlers.
"He's obviously worked a bit on his technique, but I think there are weaknesses there that we can exploit, definitely," Strauss said after the Adelaide win.