Cameron Green had indicated he was willing to open the batting for Australia in Test cricket before a back injury ruled him out for the summer.

Australia's selectors have officially declared they are looking for an opener for the Border-Gavaskar Trophy, with Steve Smith to move back to No.4 against India.

The move means Smith's time as a Test opener will last just four matches, after he put up his hand to replace David Warner at the top last summer.

AAP can reveal Smith began talks with coach Andrew McDonald about dropping back down the order as early as August, before the tour of England, where Green was injured.

At the time, Smith insisted he did not see a big difference between opening or batting at No.4, but felt Usman Khawaja and Marnus Labuschagne preferred him batting below them.

Australia had not made a definitive call on where Smith would bat at that point, and who would replace him at the top if he went back to No.4.

But it's expected Green could likely have been a candidate.

The West Australian had spent the first half of last summer preparing to open for Australia in Test cricket, before Smith's move created an opening at No.4.

And speaking before stress fractures in his back emerged, Green had revealed he was ready to move to the top of the order if Smith was to drop back down.

"It's always a thought that it may happen, and if it does happen I am very happy to put my hand up and do it," Green told AAP in August.

"Especially when you sit on the sideline for Australia, you realise how much it means to you and how much you want to get back there.

"Any time you get asked to do a role in Test cricket you are very happy to put your hand up."

Marcus Harris, Cameron Bancroft and rising star Sam Konstas loom as the most likely options to open in the first Test against India, starting on November 22.

Green is expected to miss at least six months of cricket following surgery on his back, meaning he will also sit out Australia's two-Test series in Sri Lanka.

What role Green returns to Australia's Test team in is yet to be seen, with two Tests in the Caribbean next June and a home Ashes during the 2025-26 summer.

It is possible the only spot available is at the top of the order, depending on how long Khawaja plays on, and the form of whoever comes in to open this summer.

Green had predominantly batted at No.6 in his first three years in the Test team, before averaging 53.6 at No.4 last summer.

The allrounder put much of that down to an ability to bat patiently and contend with the swinging ball, traits that are also crucial as an opener.

"If anything I was more calm at that (No.4) position," Green said in the same interview before his injury.

"It's a position I am pretty comfortable in and pretty happy in, taking my time and knowing there's a lot more time in the innings than what there is batting at No.6.

"I am very happy with the ball moving around a bit more and if I am able to take my time and get myself in and get myself moving."