The stage in Sydney is, of course, much less grand. It is not the Ashes for a start and Clarke's team had already wrapped up the three-match series. However, if the captain's call on Thursday to bowl first was questionable, it was made to look more so by the events of Friday.

There is every chance Australia will still go on to win this match, completing a whitewash and sending Michael Hussey, in terms of the result at least, out in style. They passed the Sri Lankan total late in the day but after being on the back foot at several stages, the underdog tourists will fancy their chances over the weekend. They are certainly in a far better position than pre-Test odds of $12 suggested.

Rangana Herath, in particular, will be licking his lips at a possible fourth- or fifth-day showdown with Australia's batsmen on a deck that was mooted as less friendly to spin before the match but, as it dries out further, may just return to character for the pocket-sized left-arm orthodox to exploit. It took an eternity for Mahela Jayawardene to finally throw him the ball, but he is indisputably Sri Lanka's key man.

Cruising for significant periods, via the excellent David Warner and Phillip Hughes and then Clarke, Australia's advantage was tossed away largely by their own hand. The profligacy began early and by the close of play probably only Hughes's departure, caught sharply by fill-in wicketkeeper Dinesh Chandimal while slashing Herath, was down to the opposition. The other dismissals of specialist batsmen were either run-outs or the consequence of loose shots. The hosts' long tail, a side effect of the selection of four quicks and a spinner here, was then put to the test.

It could be that shortage of genuine batsmen that comes back to bite Clarke. He has been lauded not only for his supreme batting over the past year but also for his intuitive and attacking captaincy. There was the pair of bold declarations in the Caribbean then another in the first Test in Hobart, all designed to force a result. The outcome spoke for itself: he lost only the one Test for the year - South Africa in Perth.

Clarke the tactician is, to his credit, not afraid of risk. In flirting with possible defeat to secure victory, he has demonstrated that plainly. But 21 months since he was installed in place of Ponting he might just have made his first ridgy-didge mistake. The inclusion of four fast bowlers - Peter Siddle, Mitchell Starc, Jackson Bird and Mitchell Johnson - essentially forced his hand at the toss on Thursday morning. When it dropped his way on the edge of a wicket Australia deemed a pace haven, he had little option given the make-up of his side than to send Sri Lanka in. Had Glenn Maxwell, surely worth a look ahead of the tour of India, been picked instead the captain would not have been backed into such a corner. All that probably shouldn't have mattered, but now it does.

In huge letters on the yet-to-be-named new grandstand at the SCG is an advertising slogan: 'WHAT'S YOUR PLAN B?'The same question could now be asked of Australia.

Australia has either underestimated their opponents, misread the pitch or both. Clarke's side are still strong favourites to win the match in any case. But does the end justify the means?