ALICE SPRINGS, AUSTRALIA - MARCH 30: Travis Head of the Redbacks plays a sweep shot during the Sheffield Shield final between Victoria and South Australia on March 30, 2017 in Alice Springs, Australia. (Photo by Brendon Thorne/Getty Images)

It’s fairly obvious there are only two batting positions available in Australia’s top six when the XI is picked for the first Test at the Gabba in less than a fortnight.

David Warner, Marnus Labuschagne and Steve Smith are locked in as an opener, number three and number four respectively, and the only way any of them miss out will be through injury.

Of that there can be almost no doubt.

Cameron Green too should be locked into his spot at number six. Green is the incumbent for the role and hasn’t done anything wrong to suggest he should be dropped after an indifferent debut summer last time out against India.

But then, the entire Australian team had what could be described an indifferent summer as things went from bad to worse in an eventual series loss against the Indians.

So it comes down to Usman Khawaja, Travis Head and Marcus Harris for the two spots. One of Khawaja or Harris will partner Warner at the top, while either Khawaja or Head could realistically bat at number five without a problem.

It was beginning to look for all money like the positions would be for Harris and Khawaja respectively too.

Harris scored a century against New South Wales in October, and while he hasn’t played since the November 5 Shield game against the same state, the century sent a reminder of what he can do ith the bat in hand.

Khawaja had found form too across both first class cricket and List A matches. He scored 174 and 119 in back-to-back innings against South Australia and Tasmania in two very different conditions, and while he failed in a List A game in between, he then made 70 against Western Australia.

Three big scores in four seemed to have him on the right track, and while he failed in the first innings against South Australia this week, that shouldn’t be enough to rule him out of the series.

Or, at least, it shouldn’t have been.

Khawaja enforced the follow on as Queensland captain though and after a first-innings failure, Travis Head an enormous chance to redeem himself - a chance which he took with both hands and ran away with.

After a blistering start to the summer on a bunch of roads, genuinely tough pitches have tested Head out, with just a single 50 in his last innings in games against Queensland, Western Australia and Tasmania.

Now back against Queensland, Head made just eight in the first innings to rack up his fifth failure in six innings. Those scores have gone 55, 23, 28, 9, 21 and 14, only the first of those six making any sort of traction as a good performance.

But the follow on enforced, Head belted a century to send a timely reminder to the selectors during Thursday’s Day 3.

With only 88 runs required, and Khawaja batting at four on the final day, he won’t have a chance to mount his own case, but one century from Head can’t take away from the body of work for Khawaja.

Head has been badly out of touch for much of the last month, and while he will have another chance in the Australia-Australia A clash, he may need runs there to survive, in much the same way Harris will.

One decent innings in four and not batting for a month could well and truly hurt the chances of Harris, with Khawaja quite comfortable opening.

What will work against Khawaja is the fact he isn’t opening for his state, and so selectors may not be all that keen to take a punt on the veteran to partner Warner.

But whatever the case, if it comes down to Head and Khawaja, selectors can’t allow things to be skewed based on one innings.

It’s time to assess the whole body of work, and whichever way the cookie crumbles - that’s who should be lining up at five in Brisbane.