Peter Siddle delivers the bad news about his hamstring to the selector Merv Hughes © Getty Images Enlarge
Related Links News : Smith enters revolving spin door Preview : Teams rocked by injury doubts News : Test debut makes Clint's day News : Geeves called as Siddle's standby Players/Officials: Adrian Barath | Shivnarine Chanderpaul | Nathan Hauritz | Clint McKay | Peter Siddle Series/Tournaments: West Indies tour of Australia Teams: Australia | West Indies

Australia and West Indies have both been hit by a series of injuries the day before the third Test in Perth, with Peter Siddle ruled out, Shivnarine Chanderpaul and Adrian Barath unlikely, and Nathan Hauritz also in doubt.

The problems have left Australia with one confirmed debutant, the Victoria fast bowler Clint McKay, who will replace his state team-mate Siddle. And Steven Smith, the 20-year-old batsman-legspinner, has been put on standby for Hauritz and will fly from Sydney to Perth on Tuesday night.

Hauritz took a blow to his spinning finger while fielding at training on Tuesday and although he did bowl afterwards, he suffered some soreness and will not know his fate until the morning of the match. Smith has starred with the bat for New South Wales this week, scoring a century against Queensland, but not with the ball.

Ricky Ponting said the replacement spinner would not necessarily step straight into the starting line-up if Hauritz missed out. The Tasmania fast bowler Brett Geeves joined the squad on Monday night and will be considered along with Smith if Hauritz wakes up with a swollen finger.

"There'll be a chance of that," Ponting said of a four-man pace attack. "Geeves flew in last night and trained with us this morning. There'll be that possibility but I've said for a while it's always my preference to go into a Test match with a specialist spin bowler but we'll wait and see what happens."

West Indies are likely to have two changes with the key batsmen Chanderpaul and Barath both in serious doubt. Chanderpaul is still struggling with a finger problem after being struck on the hand in Adelaide, while Barath hurt his hamstring during the second Test.

"It's not looking too good but we'll see what happens tomorrow," the captain Chris Gayle said. "Those two guys are the worry for us right now. It's a big blow going into the final Test match but having said that whoever gets that opportunity, hopefully they will make the best use of it."

Travis Dowlin is expected to come in and open with Gayle in place of Barath, while Chanderpaul's spot is likely to be taken by Narsingh Deonarine. Ponting said the injuries to Chanderpaul, who Australia found almost impossible to dismiss last year in the Caribbean, and Barath, who made a hundred on debut in Brisbane, would be a major blow for West Indies.

"That's not ideal for them," Ponting said. "Barath's looked pretty good most times he's come to the crease and we all know how much of a run scorer Chanderpaul is for them, so that's two of the better players out of their batting so that'll leave a couple of big holes. It'll be nice for Clint to be bowling to some of their younger guys, in a way."

The opportunity for McKay opened up because Siddle, who was under a cloud during the week after suffering a strain to his left hamstring in Adelaide, woke up on Tuesday with some soreness following a lengthy spell in the WACA nets the previous day. It was enough for the Australians to err on the side of caution and Siddle, who will fly home to Melbourne, will aim to be available for the Boxing Day Test against Pakistan.

"The deal was that for him to come up here and play this game it would have to be a seamless period and have no pain, no stiffness, no feeling at all of anything wrong," Australia's physio Alex Kountouris said. "He bowled yesterday and this morning he woke up and it's a little bit stiff.

"He was almost ready to play this one and he has done no harm, it's just a bit of stiffness. So we're going to go back to Melbourne now and just try a couple of little things, it's probably more coming with his back we believe, so we'll try to deal with that component of it. I'm fairly hopeful he will be okay [for Boxing Day]."

Australia are already without Ben Hilfenhaus (knee), Stuart Clark (back) and Brett Lee (elbow) from the Ashes squad, leaving Mitchell Johnson as the only fast man from that tour who is still fully fit. The loss of Hilfenhaus, who was the Man of the Match in the Gabba victory, has been the biggest blow for Australia and Kountouris said the outlook for Hilfenhaus was still uncertain.

"He has commenced bowling today so it will depend on how he is going over the next two or three times he bowls," Kountouris said. "Knee tendonitis, or tendonitis anywhere, is a bit of a grey area. Most people play with pain, it's just whether the level of the pain is severe enough to stop them doing what they have to do.

"In his case he had it throughout England and he was fine, he got through, he just got to the point where it became very painful during the Brisbane Test match. Until he has another bowl and sees how he goes we really don't know how long his prognosis is. We're hopeful he will be up but we just don't know at the moment."