Michael Clarke overcame a serious back injury to lift Australia to 6-405 when rain caused an early end to the morning session on day two of the first Test against India.

Clarke was on 85, while Steve Smith was two runs shy of his fifth Test ton when an early lunch was taken at Adelaide Oval on Wednesday.

Officials were hoping no overs would be lost and play could resume at 130pm local time.

The covers came off and India entered the field, only for another shower to delay the start of the second session.

Clarke retired hurt on 60 on Tuesday, when he was sent for scans and received injections following a flare-up of his chronic back injury.

But the skipper donned a back brace and strode onto Adelaide Oval on Wednesday, despite Australia’s team physiotherapist Alex Kountouris admitting the captain was “struggling”.

“Unfortunately it’s quite a significant back injury,” Kountouris said before play.

Clarke was clearly restricted – there was no trademark fancy footwork and he limited his shot selection to minimise twisting at the crease.

The 33-year-old grimaced regularly, but India failed to make the most of overcast conditions after Australia resumed day two at 6-354.

Clarke’s running between the wickets was understandably slow, but he and Smith kept the scoreboard ticking over with a handful of sweetly-timed boundaries.

Rain was set to delay the game at 11.26am local time, when the umpires called for the covers before changing their mind.

Shortly after, they had no choice as heavy rain started to soak the pitch.

Clarke has three degenerative discs in his lower back and every shot caused a clear pang.

“He’s showing a lot of courage … he’s trying to shield the tail from the second new ball and he just wants to be out there,” Shane Warne said while calling the game for the Nine Network.

“He’s hurting.

“Some (strokes) are going to hurt a lot more than others, but he’s in a lot of pain.”

The skipper overcame a recurring left hamstring injury to play the rescheduled first Test.

But Kountouris believed his current woes were unrelated to the hamstring issue.

“This is his right lower back. This is his old injury, what he’s had in the past,” he said.

“I don’t think it’s directly related to his hamstring, because it’s the other side.

“We believe it’s related to his old disc injuries. With that comes a lot of muscle spasms and other things that cause pain.”