Not being sure of their best playing eleven -- hours before the fourth Test beginning at the bouncy wicket at The Gabba -- is a predicament that a badly-depleted India face as they ready to take on hosts Australia in the all-important series decider.

Ace speedster Jasprit Bumrah is racing against time to get fit from his abdominal strain even as batsman Hanuma Vihari, who saw India through to a draw in the third Test, is unlikely to play due to hamstring injury.

Off-spinner Ravichandran Ashwin and batsman Mayank Agarwal too have injury worries.

The series is locked 1-1. Australia won the first Test at the Adelaide Oval while India won the second at the Melbourne Cricket Ground.

Australia, on the other hand, have worries only in the opening slot where they will feature the third opening combination of the series. Will Pucovski is out and Marcus Harris will open with David Warner. Pucovski dislocated his shoulder while fielding in Sydney, where he made an impressive first innings’ 62 on debut. The rest of the playing eleven however remains the same.

There has been very little time for a turnaround between the third and the fourth Tests, just a three-day gap.

Both the bowling sides were put under the pump in the third Test in Sydney. While the Indian bowlers bowled on all of the first four days, the Aussies were made to bowl 131 overs on the final two days.

Despite that, the hosts still seem to be far more sure about their line-up than India whose biggest concern is the lower middle-order batting and the bowling attack.

There have been talks about playing Washington Sundar. If he plays, the off-spinner could be expected to play as spin-bowling all-rounder more in the mould of Ravindra Jadeja.

India’s pace bowling attack, even with Bumrah, is very inexperienced. Without him, they will be really a rookie pace attack.

If Bumrah doesn’t play, India’s pace attack could at best feature bowlers with an overall experience of four Test matches.

Australia, with their three frontline bowlers, as well as Camron Green, will feature a pace attack that has 150 Tests in all under its belt.

The Indians are, however, unfazed. They have been mentally tough and are gearing for this Test with same courage that they showed at the SCG.

Batting coach Vikram Rathour has confirmed that the playing XI will be named on Friday itself.

“Basically, the mental toughness comes from preparation. They all have been working hard, not just for this series but for many, many years now. They all are good players,” said Rathour while speaking on Thursday morning.

“We always believed in their abilities...Even after the Sydney Test, from the coaching staff perspective what was being said was that when you have belief in preparation, it reflects in the way we play our cricket. We cannot let doubts creep in. This is how the team is playing and they have shown a lot of character. I think the reason for that is the hard work that we have put in and not only for this tour but for many years,” he added.

There are chances of rain on the second, fourth and fifth days of the Test match.

“As far as we are concerned, we are looking for a complete game. We are going to give our best,” said Rathour.

‘SMITH FEEDS OFF CRITICISM’: Meanwhile, Australian skipper Tim Paine warned on Thursday that Steve Smith “feeds off” criticism and was fired up for the high-stakes fourth Test against India, which Australia will start without injured opener Pucovski.

Smith has faced accusations he had been trying to cheat by scuffing up batsman Rishabh Pant’s guard at the crease during the tense drawn third Test at Sydney, which left the series locked at 1-1.

He strongly denied it and said he was shocked by the reaction, claiming he was simply shadow batting.

Paine, himself slammed for an ugly sledging incident during the match, said his teammate was mentally strong and determined to build on his man-of-the-match performance in Sydney, where he made 131 and 81.

“Steve is in a good frame of mind,” Paine said ahead of the clash at the Gabba starting Friday, a ground where Australia are unbeaten since 1988.

“I think we’ve seen through what he’s been through in the last three years... he’s mentally very strong, very tough. He knows sometimes he’s going to be criticised and he’s handled that supremely well.

“If anything, I think he feeds off it. His statistics speak for themselves and we’ll see the best of Steve Smith again this week.”

Commenting on Pucovski’s replacement Harris, Paine said: “He’ll come in and open the batting and looking forward to seeing what he can do. He’s a no fuss, very good player.”

Australia XI: David Warner, Marcus Harris, Marnus Labuschagne, Steve Smith, Matthew Wade, Cameron Green, Tim Paine (c & wk), Pat Cummins, Mitch Starc, Nathan Lyon, Josh Hazlewood.