Australia's pace bowling stocks take a massive hit, while Steve Smith has a mixed day and Mohammed Siraj survives by the barest of margins.

Here are the quick hits from the fourth day at the Gabba.

1. Wake up, Smudge

Before play on day four, Mitch Marsh spoke to Fox about needing to create 16 chances to wrap up India's first innings and complete the second to secure victory.

What he neglected to mention was the second part of the equation: taking those chances when they arrive.

Steve Smith certainly didn't do that when he was given a golden opportunity as KL Rahul got a healthy edge straight to him at second slip off the first ball of the day.

It was a simple catch, right into his stomach off a gentle edge and the ball simply hit him too high on the hands and bobbled out.

Smith desperately stuck a foot out to try to kick it back up to himself, missed, and stepped on first slip Usman Khawaja's toes as he stumbled back, sending Khawaja tumbling to the turf.

"That's unbelievable. Dropped one that he would never drop … and he's spiked Khawaja," former Test coach and player Darren Lehmann said in commentary for ABC Sport.

"Comedy of errors in the end. He won't get many easier than that."

It wasn't just any wicket either; Rahul was on 33 when the catch was dropped and carried on to become India's top scorer for the series and has now faced more balls than any player across two-and-a-half Tests.

2. Hoff off

Josh Hazlewood missed the second Test with a side strain but recovered in time to replace Scott Boland at the Gabba.

Australia would have wanted to have its bowling stocks full to take 16 wickets between expected rain delays over the final two days of this Test, but started day four without Hazlewood on the field.

He returned after the first couple of overs, but could only bowl one underwhelming over of his own in obvious discomfort before having to leave the field at the first drinks break.

Cricket Australia said it wasn't a recurrence of the side strain, saying later that he was struggling with his calf, another problem for the lanky quick, who has struggled with injuries over the past few years, to deal with.

The injury, which he picked up in the warm up, may rule him out for the series, with the Boxing Day Test at the MCG and the SCG Test starting on January 3.

3. Smith makes amends

As KL Rahul gradually compiled his runs, Steve Smith must have been feeling worse and worse about his calamitous drop off the first ball of the day.

Rahul, who was on 33 at the time, passed 50, 60, 70, 80 and looked well set on making a century.

But then, out of nowhere … well you know the rest. We've had this script before.

Nathan Lyon, who hadn't been as effective as he might have hoped, enticed the well-set batter into a cut that he edged to Smith, standing at first slip, who stuck his right paw out and claimed a wonderful diving catch.

It might have been 51 runs and 25.3 overs after it should have been taken, but Smith's atonement was still spectacular.

4. Rain, rain, go away

This Test match has been plagued by rain delays throughout, and day four was no different.

A slightly delayed start.

A short delay in the first session.

A longer couple of rainy spells after lunch, split by a narrow window in which 17 balls were able to be bowled.

Just before the rescheduled tea break, Mitch Starc was left frustrated by a sprinkle of rain forcing the players off.

"This is bulls***," he was seen saying at the end of his mark.

It has been the tenor at which this game has been played, the Test entirely dependant on the rhythms of nature — which isn't nearly as romantic or satisfying as it sounds.

5. A game of millimetres

Sport is often described as a game of inches.

For Mohammed Siraj it was a matter of millimetres that kept him alive in this Test.

Jadeja flicked the ball onto the leg side, with Travis Head around quickly to cut the ball off.

He threw to the non-strikers end, where Marnus Labuschagne whipped the bails off quick-smart.

Siraj looked to be home but, upon closer inspection, the Indian bowler had never grounded his bat behind the line — and it remained tantalisingly raised as he slid.

In the end, it was too close to call, with Siraj getting the benefit of the doubt.

The biggest Australia-India moments

Throughout the summer, we'll look back at some of the best stories and share our own favourite moments from Australia and India's cricket history.

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