AUSTRALIA'S selectors have been told Peter Siddle is at much greater risk of injury than when he broke down in the West Indies earlier this year, but they are tempted to pick him for what is being described in the inner sanctum as a ''grand final'' against South Africa.
The dilemma looms as the most critical faced by John Inverarity's selection panel, which has been presented with data showing that even if Siddle escapes injury in Perth, he remains at high risk of breakdown for the next month, placing him in doubt for the next series against Sri Lanka.
And, should the selectors take the gamble, the leader of the Australian attack - so ferocious and relentless in Adelaide - would be forced to play a diminished role in the match that determines whether Michael Clarke's team usurps the Proteas to top the world rankings.
Among the variables being considered are the structure of the attack - if Siddle played as part of a four-man pace attack, with all-rounder Shane Watson to provide relief - he could get away with bowling far fewer overs than he did in the first two Tests.
Even so, they would be flirting with danger given the advice to Cricket Australia from sports scientists is that fast bowlers enter the so-called ''danger zone'' when they bowl more than 80 overs in a month. Siddle has bowled an astonishing 142.5 overs since November 1, comprising two Tests and Victoria's Sheffield Shield game against Western Australia.
Siddle flew home from the West Indies in April with the beginnings of a stress fracture in his back, having entered the danger zone during the last Test against India in Adelaide. But South Africa's resilience with the bat, and James Pattinson's breakdown during the second Test in Adelaide, means much more has been demanded of him this summer.
Siddle bowled himself to near-exhaustion, and Australia to within two wickets of victory, in the second Test. As much as he dislikes the notion of being rested for a Test, he said on Wednesday he wouldn't play if he wasn't physically capable of fighting through another match.
''You never want to do that [withdraw from a Test] but you've still got to think of the end result as well, obviously I don't want to miss any Test matches but in the end if I'm struggling through tomorrow or if I don't feel 100 per cent I've got to talk to the captain, the selectors and work out what's the best,'' Siddle said on Wednesday.
''You see the hard work we went through in the last match with someone breaking down after nine overs and the efforts Hilfy [Ben Hilfenhaus] and myself had to go through to bowl those massive amount of overs. You don't want that happening again here where it's such a big game and so much riding on the line of it you want everyone to be right. So I just have to wait and see tomorrow, see how I'm feeling and make a judgment after training [on Thursday].''
The selectors will also be guided by a personal wellbeing index that requires Siddle to document his energy levels, sleep patterns and any soreness.
''It depends on the player, really,'' Siddle said of CA's contentious rest-and-rotation policy. ''I'm feeling good now, it just comes down to the player having a good chat with the coaches and the selectors and going with which way is going to be best for the team. Sometimes the line-up might say it's not going to work but if I'm feeling fit and ready to go, I'm going to give my all. I'll be ready to fight throughout the whole Test match.''
Siddle said his decision to quit meat and alcohol, combined with a punishing fitness regime, had a positive impact on his endurance and recovery.
''That's how I think it came out on the field, and I've actually recovered a lot better than I thought I would. It was obviously sore that night, but the last two days I've been waking up and feeling better and better, and I'm recovering a lot quicker. That's probably a massive part, being vegetarian is playing a big part and no alcohol has topped that off nicely. It's all working well at the moment and hopefully I can keep performing well.''
The selectors faced a similar dilemma with Pattinson last summer, and chose to pick him for the Sydney Test against India after sports scientists said he was at increased risk of injury.
Pattinson destroyed the Indian top order but broke down with a foot injury during the game, and was sidelined for the next eight weeks.