Guessing at Australia's batting order from Test to Test has become as difficult as tipping the Big 6 on a day at the races. There are always one or two dead certs, perhaps even enough for a quadrella. But correctly predicting all six winners? Good luck with that. So it is again as the Australians prepare for their final match of this campaign at The Oval, where they might become the first Australian team in 35 years to lose four Tests in an Ashes series.

Chris Rogers will open, that much is clear. David Warner will presumably partner him. Michael Clarke will probably bat at No. 4, but who's to say he won't shuffle down or up a position. Shane Watson will slot in somewhere; he suffered a groin injury in the fourth Test but bowled unscathed in the nets at The Oval on Monday, albeit largely below full pace. Usman Khawaja is unlikely to hold his place at No. 3. Steven Smith is no certainty.

Phillip Hughes might be recalled, or he may not. Ed Cowan could be, though that is highly improbable. Matthew Wade is being considered by the selectors as a specialist batsman, which in some ways makes sense given his record of two centuries and three fifties from 12 Tests. The inclusion of Wade, perhaps at No. 6, is just one of many possible Australian team permutations for The Oval Test.

Wade was bowling alongside Watson in the nets on Monday, sending through his skiddy seamers at a much nippier pace than would be expected of a small gloveman. The national selector John Inverarity has made no secret of the fact that he likes "multi-skilled" cricketers, but including Wade as a non-keeping batsman who could send down the occasional over would be something different, even for him.

Australia have occasionally played two keepers alongside each other in one-day cricket - Haddin played nine ODIs as a specialist batsmen when Adam Gilchrist had the gloves, and five of Gilchrist's early one-dayers came when Ian Healy was keeping - but it is a rarity in Test cricket. Not since Tim Zoehrer kept and Wayne Phillips batted at No. 3 in Auckland in 1986 have Australia had two glovemen in the one Test team.

Ironically, if Wade does play it will leave James Faulkner as the only man from the 18-man Ashes squad not to play a Test on the tour - ironically, that is, because taking the tour matches into account, Faulkner has topped the batting averages having been dismissed only once for 111 runs. But his only real chance of playing at The Oval would have been had Watson struggled to bowl. The Australians need to see how Watson recovers on Tuesday but they are confident he will play.

Whatever the case, it seems certain that the batting order will change - again. Not since the first two Tests of the tour of India earlier this year have they used the same top six in the same order in consecutive Tests. Not surprisingly, during that same period Australia have lost seven of eight Tests, though whether the losses cause the flux in the batting order or vice-versa is much like the chicken-or-egg debate.

From Chennai to Chester-le-Street, every specialist batsman but Rogers and Khawaja - neither of whom were in the side in India - has moved positions at least once, perhaps more. Staying still has helped Rogers, who has averaged 43 on this Ashes tour, but not Khawaja, who has 114 runs at 19.

Allan Border, Steve Waugh, Ricky Ponting and Ian Healy have all spoken out in the past couple of weeks about the need for Australia's selectors to show patience, to pick their best line-up and stick firm with it. In a losing outfit, that's easier said than done. Not to mention, how can they be sure of their best line-up if the players they choose fail to perform?

Whatever the case, if the team keeps losing and the batsmen keep failing, the order and the personnel will keep changing. Whether it's Wade, Smith, Khawaja or Hughes, this Test will be a chance for someone. Eventually at some point, someone somewhere will stand up. Somehow.