IND vs AUS: Australia head into the crucial Boxing Day Test against India with selection conundrum due to injury to key pacer, and most importantly the poor form of the top order batters.

On the injury front, there is positive development around Travis Head, whose quad concern is believed to be of a minor nature and will not hamper his participation in Melbourne, and Mitchell Marsh, who showed his readiness with the ball. But the hosts will be without pacer Josh Hazlewood.

Hazlewood, who suffered a calf strain, missed major part of the rain-hit Brisbane Test, which ended in a draw.

While that's the only injury concern for the fourth Test, starting on December 26, there are concerns regarding other players' form for the Boxing Day contest.

Australia have persisted with the top three of Usman Khawaja, newcomer Nathan McSweeney and Marnus Labuschagne for the first three Tests of the Border-Gavaskar Trophy, but the trio haven't exactly shown top form and have struggled against the new ball.

Khawaja has 63 runs at an average of 12.6, while his young opening partner McSweeney is slightly better at 72 runs at 14.4. Labuschagne, who made a fifty in the Perth Test, has scored a total of 84 runs across the three Tests at an average of 16.4.

In the Brisbane Test, openers Khawaja, McSweeney and one-drop batter Labuschagne performed below expectations before Steve Smith and in-form Head halted the slide with centuries in the first innings. The second innings was even worse with the top three managing just 13 runs.

There have been loud calls for the trio to bounce back quickly, Australia skipper Pat Cummins, expressed sympathies for the trio in the post-match presentation following the draw in Brisbane.

"I think the trend in world cricket pretty much all around the world is the top three is a really hard place to bat at the moment.

Particularly here in Australia, the wickets are tough. I think there's little snippets that have been important," Cummins was quoted as saying by ICC.

"Obviously they would be hoping to score more runs, we'd like them to score more runs, but I think they have made some important contributions that others have benefited from."

Healy says MCG Test ultimatum for top three

Despite the skipper's backing, it is uncertain if Australia go with all three for the remaining two Tests.

Legendary wicketkeeper Ian Healy has advised them to go to the basics and perform if they want to continue in the team.

"I don't see them (Australia) regressing going into Melbourne, but they are out of form, they're seriously out of form," Healy told SEN Radio.

"Questions have got to be asked of George Bailey: 'Can we get this form back? Are you confident that form will reemerge in our top three?' "Otherwise changes have to be made, and 'what suggestions might you have for us, George?' That type of thing."

Healy opined that the Melbourne Test should be Khawaja, McSweeney and Labuschagne's best chance to redeem themselves and asked the trio to get back to the basics.

"The Melbourne Test is probably the least volatile wicket they'll play on and that's their best chance. But form takes a little longer than a week to turn around, and it's just not coming for them.

"They've got to get right back to basics and strip it right back. See the ball and hit it, don't care where your feet go. That's the first step, just get some clarity in your head," said Healy.

Who will be Australia's replacement pick in the top order?

If Australia think of a change to their top order, young batter Sam Konstas, who was initially believed to be in line for an opening role for the hosts, is the most likely option.

While his poor run into the Test series ruled him out of contention, his recent form, including a hundred against India in a tour game for the Prime Minister's XI and subsequent scores of 88 (in Sheffield Shield) and 56 in Big Bash League make him a potential candidate for Australia.

Who will replace injured Josh Hazlewood?

For Hazlewood, Australia have a ready made replacement in Scott Boland, who starred in the Adelaide Test with his 5/105. But, the hosts will also be look to add support to the pace attack with the likes of Lance Morris, Jhye Richardson, and Mark Steketee in the reckoning.

Australia must avoid defeat in Melbourne to keep their hopes alive of taking back the Border-Gavaskar Trophy. India too will keep their hopes alive for the Lord's title clash next year should they win the Boxing Day Test before heading to Sydney for the finale.